Golf club

ABSTRACT

A golf club includes a head; a shaft; and a grip, wherein the head includes a front member and a back member detachably mounted to the front member.

This application is a Divisional of co-pending application Ser. No.14/581,777 filed on Dec. 23, 2014, which is a Divisional of applicationSer. No. 13/234,208 filed on Sep. 16, 2011, now abandoned. ApplicationSer. No. 13/234,208 claims priority under 35 U.S.C. §119(a) on PatentApplication No. 2010-208923 filed in JAPAN on Sep. 17, 2010 and PatentApplication No. 2011-166179 filed in JAPAN on Jul. 29, 2011. The entirecontents of each of the above applications are hereby incorporated byreference.

BACKGROUND OF THE INVENTION Field of the Invention

The present invention relates to a golf club. In particular, the presentinvention relates to a golf club having adjustability.

Description of the Related Art

Golf players select and use golf clubs suited to themselves. The numberof golf clubs capable of being used during playing golf is 14 in respectof the Golf Rules. The golf players usually select 14 clubs and make around.

However, a condition may be varied according to days even in the samegolf player. Setting of a golf course also has an influence on selectionof the golf club. Weather also has an influence on the selection of thegolf club. In order to deal with a plurality of golf courses, it isadvantageous to prepare changing golf clubs in addition to 14 clubs tobe used. Similarly, in order to deal with weather change, it isadvantageous to prepare changing golf clubs. In order to improve adegree of freedom of selection, it is advantageous to prepare changinggolf clubs.

In the golf club having adjustability, a specification can be adjusted.One golf club having adjustability can be adjusted to a plurality ofspecifications. The adjustability can eliminate the use of the changinggolf club.

A golf club having adjustability has been proposed. Japanese PatentApplication Laid-Open No. 9-201433 discloses a golf club having avariable loft angle. Japanese Patent Application Laid-Open No.2004-267460 discloses a golf club having an adjustable face angle. US2006/0293115 discloses a structure where a head is easily mounted anddetached to and from a shaft. An embodiment in which a shaft axisinclined to a hosel axis is shown in FIG. 17 of US 2006/0293115. In theembodiment of FIG. 17 of US 2006/0293115, a loft angle, a lie angle, anda face angle are varied in relation to each other due to acircumferential position of a sleeve.

SUMMARY OF THE INVENTION

It was found that there is room for improvement in the adjustability inthe conventional technique.

It is an object of the present invention to provide a golf club havingexcellent adjustability.

A golf club of the present invention comprises at least one adjustingmechanism. In the golf club, at least two specifications can be adjustedindependently of each other.

Preferably, a head, a shaft, a grip, or a joined part therebetween hasan adjusting mechanism (1). The head, the shaft, the grip, or the joinedpart has further other adjusting mechanism (2). Preferably, theadjusting mechanism (1) and the adjusting mechanism (2) can workindependently of each other. The joined part means a joined part betweenthe head and the shaft, and a joined part between the shaft and thegrip.

Preferably, the adjusting mechanism (1) or the adjusting mechanism (2)is located at a place other than a hosel part.

Preferably, the adjusting mechanism (1) and the adjusting mechanism (2)are located at places other than a hosel part.

Preferably, all the adjusting mechanisms are located at places otherthan a hosel part.

Preferably, in the golf club, the two or more specifications selectedfrom a loft angle, a lie angle, a face angle, a face area, a position ofa center of gravity of a head, a swingweight, a club length, a positionof a center of gravity of a club, a frequency of the club, a clubweight, a head shape, a head volume, a head weight, a flex of a shaft, aflex point of a shaft, a torque of the shaft, flexural rigiditydistribution of the shaft, torsional rigidity distribution of the shaft,a shaft weight, weight distribution of the shaft, a position of a centerof gravity of the shaft, a length of the shaft, a grip outer diameter, agrip weight, a position of a center of gravity of a grip, a grip length,a specification of a face groove, a face progression, a moment ofinertia of the head, a moment of inertia of the club, a coefficient ofrestitution of the head to a ball, and a friction coefficient of thehead to the ball can be adjusted independently of each other.

The number of the specifications capable of being adjusted independentlyof each other may be equal to or greater than 3, and furthermore equalto or greater than 4.

Preferably, the plurality of specifications includes one or morespecific specifications selected from a loft angle, a lie angle, a clublength, and a club weight. An adjustment range is equal to or greaterthan a width corresponding to two-number clubs in all the specificspecifications.

A golf club set of the present invention comprises the plurality of golfclubs.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a head provided with an adjustingmechanism M1 (front member changing mechanism);

FIG. 2 is an exploded view of the head of FIG. 1;

FIG. 3 is a view for explaining change of the front member;

FIG. 4 is a view of the head of FIG. 1, as viewed from a sole side;

FIG. 5 is a perspective view of the head provided with an adjustingmechanism M2 (face plate changing mechanism);

FIG. 6 is a view for explaining change of a face plate,

FIG. 7 is a view showing a golf club provided with an adjustingmechanism M3 (club length adjusting mechanism);

FIG. 8 is a view for explaining adjustment of a club length,

FIG. 9 is a view showing a golf club provided with an adjustingmechanism M4 (lie angle adjusting mechanism);

FIG. 10 is a view of the golf club of FIG. 9, as viewed from a soleside;

FIG. 11 is a cross sectional view of the golf club of FIG. 9;

FIG. 12 is a cross sectional view taken along line Cs1-Cs1 of FIG. 11, across sectional view taken along line Cs2-Cs2, and a cross sectionalview taken along line Cs3-Cs3;

FIG. 13 is a view for explaining adjustment of a lie angle;

FIG. 14 is a view showing a golf club provided with an adjustingmechanism M4 and an adjusting mechanism M5;

FIG. 15 is a view of the golf club of FIG. 14, as viewed from a soleside;

FIG. 16 is a view showing a golf club provided with an adjustingmechanism M4, an adjusting mechanism M5, and an adjusting mechanism M6;

FIG. 17 is a cross sectional view of a golf club provided with anadjusting mechanism M6;

FIG. 18 is a view of a golf club provided with an adjusting mechanismM7;

FIG. 19 is an exploded view of the golf club of FIG. 18;

FIG. 20 is a cross sectional view of the golf club of FIG. 18;

FIG. 21 is a perspective view of a sleeve used for the golf club of FIG.18;

FIG. 22 is a cross sectional view of a first sleeve;

FIG. 23 is a cross sectional view of a second sleeve;

FIG. 24 is an exploded perspective view of a golf club head providedwith an adjusting mechanism M8;

FIG. 25 is a view for explaining change of a back member;

FIG. 26 is a view showing a golf club provided with an adjustingmechanism M9;

FIG. 27 is a cross sectional view of FIG. 26;

FIG. 28 is a cross sectional view of the golf club taken along lineF28-F28 of FIG. 27;

FIG. 29 is a view showing a golf club provided with an adjustingmechanism M10;

FIG. 30 is a cross sectional view of FIG. 29;

FIG. 31 is an exploded view of FIG. 29;

FIG. 32 is an exploded view of other golf club provided with anadjusting mechanism M10;

FIG. 33 is an exploded perspective view of a golf club head providedwith an adjusting mechanism M1 and an adjusting mechanism M11;

FIG. 34 is a view of the head of FIG. 33, as viewed from a crown side;

FIG. 35 is an exploded perspective view of a head provided with anadjusting mechanism M12;

FIG. 36 is an exploded view of a club provided with an adjustingmechanism M6 and an adjusting mechanism M10;

FIG. 37 is a bottom view of a golf club provided with an adjustingmechanism M13;

FIG. 38 is a perspective view of a golf club head provided with anadjusting mechanism M14;

FIG. 39 is an exploded perspective view of the head of FIG. 38;

FIG. 40 is a cross sectional view of the head of FIG. 38;

FIG. 41 is a plan view of a golf club head provided with an adjustingmechanism M15;

FIG. 42 is a cross sectional view taken along line F41-F41 of FIG. 41;and

FIG. 43 is a bottom view of the head of FIG. 41.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention will be described below in detail based onpreferred embodiments with reference to the drawings.

An adjusting mechanism in the present invention satisfies the Golf Rulesdefined by Royal and Ancient Golf Club of Saint Andrews (R&A). That is,the adjusting mechanism in the present invention satisfies requirementsspecified in “1b adjustability” in “1 Club” of “Appendix II design ofclub” defined by R&A. The requirements defined by the “1b adjustability”are the following items (i), (ii), and (iii):

(i) the adjustment cannot be readily made;

(ii) all adjustable parts are firmly fixed and there is no reasonablelikelihood of them working loose during a round; and

(iii) all configurations of adjustment conform with the Rules.

FIG. 1 shows a head 2. The head 2 is provided with an adjustingmechanism M1 capable of being used for the present invention.Preferably, the adjusting mechanism M1 is used with other adjustingmechanisms independent of each other.

Although not shown in the drawings, a golf club provided with the head 2is provided with the head 2, a shaft and a grip. The head 2 is a woodtype golf club head.

FIG. 2 is an exploded perspective view of the head 2. The head 2 has afront member 4, a back member 6, and a connecting member 8. The frontmember 4 is connected to the back member 6 by the connecting member 8.The front member 4 is connected to the back member 6 in a state where nogap substantially exists. The hollow head 2 is completed by theconnection.

The front member 4 has a face surface 10. The front member 4 has thewhole face surface 10. Although not shown in the drawings, the frontmember 4 has a screw hole into which the connecting member 8 is screwed,and a thick part for forming the screw hole. The front member 4 isapproximately cup-shaped as a whole. Although illustration is omitted,face grooves are formed in the face surface 10.

The back member 6 has a hosel part 12. The hosel part 12 has a shafthole 14. The back member 6 has a through hole 16 through which theconnecting member 8 passes, and a thick part 18 for forming the throughhole 16. The through hole 16 is formed on each of a toe side and heelside of the head 2. The thick part 18 is also formed on each of the toeside and heel side of the head 2. Positions of the through hole 16 andthick part 18 are not restricted.

The back member 6 has a protruding part 20. In the embodiment, aplurality of (two) protruding parts 20 is provided. The protruding parts20 protrude forward from an opening part of the back member 6. Theprotruding parts 20 facilitate position adjustment of the front member4. The protruding parts 20 facilitate screwing between the front member4 and the back member 6.

The heel side through hole 16 is formed on the heel side from the shafthole 14. The heel side thick part 18 is formed on the heel side from theshaft hole 14. The disposal can contribute to shortening of a length ofthe through hole 16. The disposal can contribute to lessening of avolume of the thick part 18. The disposal can contribute tominiaturizing of a screw mechanism.

The connecting member 8 is a screw. The front member 4 is connected tothe back member 6 by the connecting member 8.

The head 2 has the adjusting mechanism M1. The adjusting mechanism M1 isa screwing mechanism between the front member 4 and the back member 6.The adjusting mechanism M1 can change the front member 4.

A changing front member E4 is shown with the head 2 in FIG. 3. Achanging front member E41 and other changing front member E42 are shownas the changing front member E4 in FIG. 3. The changing front member E41and the changing front member E42 can be connected to the back member 6by the connecting member 8. A golf club with an adjusting functionincludes the head 2 and the at least one changing front member E4.

For example, a loft angle (real loft angle) is changed by changing thefront member 4 to the changing front member E4. For example, a faceangle is changed by changing the front member 4 to the changing frontmember E4.

Examples of specifications capable of being adjusted by the adjustingmechanism M1 include a loft angle, a face angle, a face area, and a faceprogression. Each of these specifications can be independently adjustedin the adjusting mechanism M1. Furthermore, in the adjusting mechanismM1, a coefficient of restitution of the head to a ball, and a frictioncoefficient of the head to the ball can be adjusted. The coefficient ofrestitution of the head to the ball can be adjusted by, for example,changing the front member to another changing front member havingrigidity different from that of the front member. The frictioncoefficient of the head to the ball can be adjusted by, for example,changing the front member to another changing front member having a facesurface having surface roughness different from that of the frontmember.

Examples of adjustments of the specifications by the adjusting mechanismM1 include the following adjustments:

(adjustment 1 a) a loft angle is changed and a face angle is notsubstantially varied;

(adjustment 1 b) a loft angle is changed and a face angle is alsochanged;

(adjustment 1 c) a loft angle is not substantially changed but a faceangle is changed;

(adjustment 1 d) a face area is changed, and a loft angle and a faceangle are not varied; and

(adjustment 1 e) a face progression is changed, and a loft angle and aface angle are not varied.

Although the adjusting mechanism M1 is applied to the wood type golfclub head, the adjusting mechanism M1 may be used also for other typegolf clubs (iron type, utility type, and putter type golf clubs or thelike).

FIG. 5 is an exploded perspective view of a head 30 provided with anadjusting mechanism M2 according to other embodiment. FIG. 6 is a crosssectional view of the head 30. Although not shown in the drawings, agolf club provided with the head 30 is provided with a shaft and a grip.The head 30 is an iron type golf club head. Preferably, the adjustingmechanism M2 is used with other adjusting mechanism.

The head 30 has a face plate 32, a head body 34, and a connecting member36. The face plate 32 is connected to the head body 34 by the connectingmember 36. The face plate 32 is connected to the head body 34 in a statewhere no gap substantially exists. The head 30 having a cavity 38 (seeFIG. 6) formed in a back face is completed by the connection. In thehead 30, a plane p1 provided on a back surface of the face plate 32 isbrought into surface contact with a plane p2 provided on a front surfaceof the head body 34 (see FIG. 6).

The face plate 32 has a face surface 40. The face plate 32 has the wholeface surface 40. Although not shown in the drawings, the face plate 32has a screw hole into which the connecting member 36 is screwed. Theface plate 32 is a plate-shaped as a whole. Face grooves 42 are formedin the face surface 40.

The head body 34 has a hosel part 44. The hosel part 44 has a shaft hole46. The head body 34 has a through hole 48 through which the connectingmember 36 passes. The through hole 48 is formed on each of a toe sideand heel side of the head body 34. A position of the through hole 48 isnot restricted.

The connecting member 36 is a screw. The face plate 32 is connected tothe head body 34 by the connecting member 36.

The head 2 has an adjusting mechanism M2. The adjusting mechanism M2 isa screwing mechanism between the face plate 32 and the head body 34. Theadjusting mechanism M2 can change the face plate 32.

FIG. 6 shows a cross sectional view of a changing face plate E32 with across sectional view of the head 30. A first changing face plate E321and a second changing face plate E322 are shown as the changing faceplate E32 in FIG. 6. The changing face plate E32 can be connected to thehead body 34 by the connecting member 36. A golf club with an adjustingfunction includes the head 30 and at least one changing face plate E32.

For example, a loft angle (real loft angle) is changed by changing theface plate 32 to the changing face plate E32. For example, aspecification of the face groove is changed by changing the face plate32 to the changing face plate E32.

Examples of specifications capable of being adjusted by the adjustingmechanism M2 include a loft angle, a specification of the face groove, aface progression, and a friction coefficient of a head to a ball. Eachof these specifications can be independently adjusted in the adjustingmechanism M2.

Examples of adjustments of the specifications by the adjusting mechanismM2 include the following adjustments:

(adjustment 2 a) a loft angle is changed, and a specification of a facegroove is not substantially varied;

(adjustment 2 b) a loft angle is changed, and a specification of a facegroove is also changed;

(adjustment 2 c) a loft angle is not substantially changed, and aspecification of a face groove is changed; and

(adjustment 2 d) a face progression is changed, and specifications of aloft angle and a face groove are not changed.

Although the adjusting mechanism M2 is applied to the iron type golfclub head, the adjusting mechanism M2 may be used also for other typegolf clubs (wood type, utility type, and putter type golf clubs or thelike).

FIG. 7 shows a golf club 50 according to other adjusting mechanism. Thegolf club 50 is provided with ahead 52, a shaft 54, a sleeve 56, and agrip (not shown). The head 52 is a wood type golf club head. The shaft54 is tube-shaped.

As described later, the golf club 50 has an adjusting mechanism M3.Preferably, the golf club 50 has other adjusting mechanisms independentof each other, with the adjusting mechanism M3.

The golf club 50 has a plurality of connecting members 58. The golf club50 of the embodiment has three connecting members 58 (see FIG. 7). Thegolf club 50 has a first connecting member 581, a second connectingmember 582, and a third connecting member 583 as the connecting members58.

FIG. 8 is a cross sectional view of the golf club 50. A section of ahosel portion is shown in FIG. 8. A left side (configuration S1) of FIG.8 shows a state where the first connecting member 581 is used. A center(configuration S2) of FIG. 8 shows a state where the second connectingmember 582 is used. A right side (configuration S3) of FIG. 8 shows astate where the third connecting member 583 is used.

The head 52 has a hosel hole 60. The sleeve 56 is inserted into thehosel hole 60. A cross sectional shape of the hosel hole 60 correspondsto a cross sectional shape of an outer surface of the sleeve 56.

The sleeve 56 has a shaft hole 62 and a screw hole 63. The shaft hole 62is opened upward. The screw hole 63 is downwardly opened.

As shown in FIG. 8, a tip part of the shaft 54 is inserted into theshaft hole 62. The sleeve 56 is fixed to the tip part of the shaft 54.The sleeve 56 is bonded to the tip part of the shaft 54.

An outer surface 66 of the sleeve 56 has a portion having a noncircularcross sectional shape. In the embodiment, the outer surface 66 of thesleeve 56 has a hexagonal cross sectional shape. Meanwhile, the hoselhole 60 also has a noncircular (hexagonal) cross sectional shape.Rotation of the sleeve 56 to the hosel hole 60 is regulated by thesenoncircular cross sectional shapes.

The outer surface of the sleeve 56 and the hosel hole 60 may have acircular cross sectional shape. Regulation of relative rotation can bealso achieved by only the connecting member 58.

The connecting member 58 has a head part r1, an axis part r2, and ascrew part r3. The axis part r2 is provided between the head part r1 andthe screw part r3.

The plurality of connecting members 58 has different lengths. Thedifferent lengths are achieved by a difference in the length of the axispart r2.

As shown in FIG. 8, the screw part r3 of the connecting member 58 isconnected to the screw hole 63 of the sleeve 56. Withdrawal of thesleeve 56 from the shaft hole 62 is prevented by the screw connection.

As shown in FIG. 8, an insertion length Ls (see FIG. 8) of the sleeve 56to the shaft hole 62 is varied depending on the connecting member 58 tobe used. A club length is changed due to the variation.

The golf club 50 has an adjusting mechanism M3. The adjusting mechanismM3 is an changing mechanism of a shaft insertion length.

For example, the club length is changed by the adjusting mechanism M3.For example, a swingweight is changed by the adjusting mechanism M3.Examples of adjustments of the specifications by the adjusting mechanismM3 include the following adjustments:

(adjustment 3 a) a club length is changed, and a swingweight is notsubstantially varied; and

(adjustment 3 b) a club length is changed, and a swingweight is alsochanged.

Examples of means for realizing the (adjustment 3 a) include reducing aweight of a longer connecting member 58. Examples of the means includeusing a material having smaller specific gravity for a longer connectingmember 58, and reducing an outer diameter of an axis part r2 of a longerconnecting member 58.

Although the adjusting mechanism M3 is applied to the wood type golfclub, the adjusting mechanism M3 may be used also for other type golfclubs (iron type, utility type, and putter type golf clubs or the like).

FIG. 9 shows a golf club 70 according to other adjusting mechanism. FIG.10 is a view of the golf club 70, as viewed from a sole side. FIG. 11 isa cross sectional view of a vicinity of a hosel of the golf club 70.FIG. 12 is a cross sectional view in each of positions shown in FIG. 11.The golf club 70 is provided with a head 72, a shaft 74, a sleeve 76, aconnecting member 78 (see FIG. 11), and a grip (not shown). The head 72is a wood type golf club head. The shaft 74 is tube-shaped.

As described later, the golf club 70 has an adjusting mechanism M4.Preferably, the golf club 70 has further other adjusting mechanismindependent of the adjusting mechanism M4.

The head 72 has a hosel part 73. The hosel part 73 has a sleeveinsertion hole 75 (see FIG. 11).

The sleeve 76 is bonded to the shaft 74. The sleeve 76 has a screw hole77. The screw hole 77 is formed in a bottom surface 79 of the sleeve 76.

Furthermore, the golf club 70 has a plurality of sleeve supportingmembers 80 (see FIG. 11). The golf club 70 has a first sleeve supportingmember 801, a second sleeve supporting member 802, and a third sleevesupporting member 803 as the sleeve supporting members 80.

The connecting member 78 is a screw. The connecting member 78 has a headpart r1 and a screw part r3 (see FIG. 11). A concave part 81 for axiallyrotating the connecting member 78 is formed in the head part r1 of theconnecting member 78 (see FIG. 10). The concave part 81 has anoncircular cross sectional shape.

The connecting member 78 is screw-connected to the screw hole 77.Retention of the shaft 74 is achieved by the screw connection.

The golf club 70 has the adjusting mechanism M4. The adjusting mechanismM4 can adjust a lie angle. The golf club 70 of the embodiment can beadjusted to three lie angles. The lie angle is adjusted by changing adirection of a shaft axis line. The sleeve insertion hole 75 does notdisturb adjustment of the lie angle.

A shaft axis line in the case of a first lie angle is represented byreference character LS (see FIGS. 9 and 11). A shaft axis line in thecase of a second lie angle is represented by reference character LF. Ashaft axis line in the case of a third lie angle is represented byreference character LU.

The head 72 has a plurality of holding holes h1. In the embodiment, thehead 72 has a first holding hole h11, a second holding hole h12, and athird holding hole h13. FIG. 11 shows profile lines of the holding holesh1, as viewed from the lower side of the head 72, in addition to a crosssectional view of the golf club 70. A central axis line of the firstholding hole h11 coincides with the shaft axis line LS. A central axisline of the second holding hole h12 coincides with the shaft axis lineLF. A central axis line of the third holding hole h13 coincides with theshaft axis line LU.

Each of the holding holes h1 is positioned so that a central axis lineof (the head part r1 of) the connecting member 78 coincides with aposition of any one of the plurality of shaft axis lines.

As shown in FIG. 11, the plurality of holding holes h1 is mutually andpartially overlapped. Adjustment interval of the lie angle can bereduced by the partial overlapping. The lie angle can be delicatelyadjusted by the partial overlapping.

The head 72 has a plurality of insertion holes h2. Into the insertionholes h2, (the screw part r3 of) the connecting member 78 is inserted.In relation to the position of the section, the insertion holes h2 donot appear in the cross sectional view of FIG. 11. In the embodiment,the head 72 has a first insertion hole h21, a second insertion hole h22,and a third insertion hole h23. The profile lines of the insertion holesh2, as viewed from the lower side of the head 72 are also shown. Acentral axis line of the first insertion hole h21 coincides with theshaft axis line LS. A central axis line of the second insertion hole h22coincides with the shaft axis line LF. A central axis line of the thirdinsertion hole h23 coincides with the shaft axis line LU.

As shown in FIG. 11, the plurality of insertion holes 12 is mutually andpartially overlapped. Adjustment interval of the lie angle can bereduced by the partial overlapping. The lie angle can be delicatelyadjusted by the partial overlapping.

The holding hole h1 and the insertion hole h2 are continuous. A diameterof the holding hole h1 is greater than that of the insertion hole h2. Abump surface d1 exists on a boundary between the holding hole h1 and theinsertion hole h2. The bump surface d1 abuts on a bump surface d2 of theconnecting member 78.

As shown in FIGS. 11 and 12, the sleeve supporting member 80 has athrough hole 88 and an outer surface 90. A through hole 88 of a firstsleeve supporting member 801 corresponds to the shaft axis line LS. Athrough hole 88 of a second sleeve supporting member 802 corresponds tothe shaft axis line LF. A through hole 88 of a third sleeve supportingmember 803 corresponds to the shaft axis line LU.

An outer surface 90 of the sleeve supporting member 80 is a screw. Ascrew (female screw) 92 capable of being connected to the screw (malescrew) of the outer surface 90 is formed in an inner surface of thesleeve insertion hole 75 (see FIG. 11). The sleeve supporting member 80is fixed to the sleeve insertion hole 75 by screw connection. The screwconnection may be absent. For example, the outer surface 90 of thesleeve supporting member 80 may have a noncircular cross sectionalshape, and the cross sectional shape of the inner surface of the sleeveinsertion hole 75 abutting on the outer surface 90 also may correspondto the cross sectional shape of the outer surface 90. In this case,rotation of the sleeve supporting member 80 to the sleeve insertion hole75 is prevented due to the noncircular cross sectional shape.

The sleeve supporting member 80 supports the sleeve 76 along apredetermined axial direction. Simultaneously, the sleeve supportingmember 80 disturbs relative rotation of the sleeve 76 and the sleeveinsertion hole 75.

FIG. 13 shows states of three lie angles. A left side (configuration S4)of FIG. 13 shows a cross sectional view when the shaft axis line LU isemployed. In this case, the third sleeve supporting member 803 of theplurality of sleeve supporting members 80 is used. The holding hole h13is used as the holding hole h1. The insertion hole h23 is used as theinsertion hole h2. In the configuration S4, the lie angle iscomparatively upright. That is, the lie angle is comparatively great.

A center (configuration S5) of FIG. 13 shows a cross sectional view whenthe shaft axis line LS is employed. In this case, the first sleevesupporting member 801 of the plurality of sleeve supporting members 80is used. The holding hole h11 is used as the holding hole h1. Theinsertion hole h21 is used as the insertion hole h2.

A right side (configuration S6) of FIG. 13 shows a cross sectional viewwhen the shaft axis line LF is employed. In this case, a second sleevesupporting member 802 of the plurality of sleeve supporting members 80is used. The holding hole h12 is used as the holding hole h1. Theinsertion hole h22 is used as the insertion hole h2. In theconfiguration S6, the lie angle is comparatively flat. That is, the lieangle is comparatively small.

In the golf club 70, support of the sleeve 76 in each of the lie angles(each of the shaft axis lines) is achieved by the sleeve supportingmember 80 and the holding hole h1. The support of the sleeve 76 in eachof the lie angles may be achieved by only the sleeve supporting member80. The support of the sleeve 76 in each of the lie angles may beachieved by only the holding hole h1. In respect of alleviatingdimensional accuracy of the hosel part, the support of the sleeve 76 ineach of the lie angles is preferably achieved by either the sleevesupporting member 80 or the holding hole h1. In respect of alleviatingthe dimensional accuracy of the hosel part, a resin is also preferablyused as a material of the sleeve supporting member 80. The sleevesupporting member 80 made of the resin is suitable for supporting thesleeve 76 while being deformed so as to absorb a dimensional gap.

In the golf club 70, rotation stopping of the sleeve 76 is achieved bythe sleeve supporting member 80 and the connecting member 78. Therotation stopping of the sleeve 76 may be achieved by only the sleevesupporting member 80. The rotation stopping of the sleeve 76 may beachieved by only the connecting member 78. When the connecting member 78is made to function as the rotation stopping of the sleeve 76, theconnecting member 78 is preferably tightened by a force received from aball at hitting the ball. When the connecting member 78 is made tofunction as the rotation stopping of the sleeve 76, the holding hole h1and the head part r1 preferably have a noncircular cross sectionalshape, to prevent relative rotation of the holding hole h1 and the headpart r1.

FIGS. 14 and 15 show a golf club 100 according to other adjustingmechanism. FIG. 15 is a view, as viewed from a sole side. The golf club100 is provided with a head 102, a shaft 74, a sleeve 76, a connectingmember 78 (see FIG. 15), and a grip (not shown). The head 102 is a woodtype golf club head. The shaft 74 is tube-shaped.

The head 102 has the above-mentioned adjusting mechanism M4. Thedescription of the adjusting mechanism M4 is omitted.

Furthermore, the head 102 has an adjusting mechanism M5. The adjustingmechanism M5 is a center-of-gravity position adjusting mechanism. Thehead 102 has a weight body 104 and a disposing hole Wh as the adjustingmechanism M5. As shown in FIG. 15, in the embodiment, a plurality ofdisposing holes Wh are formed. These disposing holes Wh are formed in asole 106 of the head 102.

The disposing hole Wh is a screw hole. The weight body 104 is a screw.The weight body 104 is screwed into the disposing holes Wh. The positionof the center of gravity of the head is adjusted depending on thedisposing hole Wh in which the weight body 104 is located.

Examples of specifications capable of being adjusted by the adjustingmechanism M5 include a position of a center of gravity of a head and amoment of inertia of the head.

Examples of adjustments of the specifications by the adjusting mechanismM5 include the following adjustments:

(adjustment 5 a) Although a distance of a center of gravity is changed,a depth of the center of gravity is not substantially varied, and aheight of the center of gravity is not also substantially varied;

(adjustment 5 b) All of a distance of a center of gravity, a depth ofthe center of gravity, and a height of the center of gravity are varied;and

(adjustment 5 c) A distance of a center of gravity is changed; any oneof a depth of the center of gravity and a height of the center ofgravity is varied; and the other is not substantially varied.

As shown in FIG. 15, in the embodiment, the plurality of disposing holesWh is substantially aligned along a toe-heel direction. That is, acentral axis line SP1 of a first disposing hole Wh1, a central axis lineSP2 of a second disposing hole Wh2, and a central axis line SP3 of athird disposing hole Wh3 are aligned along the toe-heel direction. Inthe embodiment, when disposal of the weight body 104 is changed, adistance of a center of gravity is mainly varied by the disposal, and adepth of the center of gravity is hardly varied. Specifically, when anamount of variation of the depth of the center of gravity is defined asCd (mm) and an amount of variation of the distance of a center ofgravity is defined as Cs (mm), a ratio (Cd/Cs) is preferably equal to orless than 0.2, and more preferably equal to or less than 0.1. In thiscase, the distance of the center of gravity can be selectively adjusted.It is useful to selectively adjust the distance of the center of gravityin order to adjust the direction of the face in impact.

Although the adjusting mechanism M5 is applied to the wood type golfclub head, the adjusting mechanism M5 may be used also for other typegolf clubs (iron type, utility type, and putter type golf clubs or thelike).

FIG. 16 shows a golf club 110 according to other adjusting mechanism.The golf club 110 is provided with a head 102, a shaft 74, a sleeve 76,a connecting member 78 (not shown), and a grip 112.

The head 102 has the above-mentioned adjusting mechanism M4 andadjusting mechanism M5. The descriptions of the adjusting mechanism M4and the adjusting mechanism M5 are omitted.

The grip 112 has a main body 114, a weight body Wg, and a holding body118. Furthermore, the grip 112 has a cover 120.

The holding body 118 has a screw hole 122. The holding body 118 isdisposed medially in the shaft 74. The holding body 118 is bonded to aninner surface of the shaft 74.

The weight body Wg is detachably mounted to the holding body 118. Themounting/demounting is achieved by a screw mechanism.

The main body 114 is made of rubber. A concave part 124 is formed in avicinity of a back end part of the main body 114. The concave part 124is a circumferential groove. The cover 120 has a convex part 126corresponding to the concave part 124. The convex part 126 is a flange.The main body 114 made of rubber can be deformed, to fit the convex part126 into the concave part 124. The cover 120 is detachably mounted.

The grip 112 has a weight adjusting mechanism as an adjusting mechanismM6. The weight adjusting mechanism is achieved by changing the weightbody Wg. The swingweight can be adjusted by changing the weight body Wgto other weight body Wg having a weight different from that of theweight body Wg. For example, the swingweight is lightened by changing afirst weight body Wg1 to a second weight body Wg2 having a weightgreater than that of the first weight body Wg1. For example, theswingweight is weighted by changing the first weight body Wg1 to a thirdweight body Wg3 having a weight smaller than that of the first weightbody Wg1. The adjusting mechanism M6 has at least two weight bodies Wghaving weights different from each other.

Examples of specifications capable of being adjusted by the adjustingmechanism M6 include a swingweight, a moment of inertia of a club, agrip weight, and a position of a center of gravity of a grip.

Although the adjusting mechanism M6 is applied to the wood type golfclub head, the adjusting mechanism M6 may be used also for other typegolf clubs (iron type, utility type, and putter type golf clubs or thelike).

FIG. 18 shows a golf club 130 according to other adjusting mechanism.FIG. 19 is an exploded view of the golf club 130. FIG. 20 is a crosssectional view of the golf club 130.

As described later, the golf club 130 has an adjusting mechanism M7.Preferably, the golf club 130 further has other adjusting mechanismindependent of the adjusting mechanism M7.

The golf club 130 has a head 132, a shaft 134, a sleeve Sv, a screwcylinder 135, and a connecting member 136. The screw cylinder 135 isfixed to a tip of the shaft 134. A grip (not shown) is mounted to a backend of the shaft 134.

The head 132 has a head body 138 and an engaging member 140. The headbody 138 has a hosel hole 142 into which the sleeve Sv is inserted, anda through hole 144 into which the connecting member 136 is inserted. Thethrough hole 144 penetrates a bottom part of the hosel hole 142. Thehead body 138 has a sole hole 146 opened in a sole (see FIG. 20). Thesole hole 146 is continuous with the hosel hole 142 via the through hole144.

The engaging member 140 is fixed to the head body 138 (see FIG. 20). Thefixing method is not restricted, and examples thereof include bonding,welding, fitting, and a combination thereof. The engaging member 140 isintroduced into the hosel hole 142 from an upper side opening of thehosel hole 142. The engaging member 140 is fixed to the bottom part ofthe hosel hole 142.

FIG. 21 is a perspective view of the sleeve Sv. FIG. 22 is a crosssectional view of the sleeve Sv.

The sleeve Sv has a shaft insertion hole 150 and a lower side hole 152.The shaft insertion hole 150 is opened to an upper side. The lower sidehole 152 is opened to a lower side. The lower side hole 152 is disposedon a lower side of the shaft insertion hole 150.

The sleeve Sv has an engaging part 162. The engaging part 162 has aconvex part t1. A plurality of convex parts t1 is aligned in thecircumferential direction. The convex parts t1 are equally disposed inthe circumferential direction. The convex parts t1 are disposed at every30 degrees.

Although not shown in the drawings, an engaging surface capable of beingengaged with the engaging part 162 of the sleeve Sv is formed in aninner surface of the engaging member 140. A cross sectional shape of theengaging surface corresponds to that of an outer surface of the engagingpart 162. Rotation of the sleeve Sv to the hosel hole 142 is preventedby engagement between the engaging surface (inner surface) of theengaging member 140 and the engaging part 162.

The shaft insertion hole 150 is a screw hole. That is, the shaftinsertion hole 150 is a female screw.

The screw cylinder 135 is approximately cylindrical-shaped as a whole.An outer surface of the screw cylinder 135 is a screw. The outer surfaceof the screw cylinder 135 is a male screw. An inner surface 154 of thescrew cylinder 135 is a circumferential surface. An outer surface 156 ofthe shaft 134 is bonded to the inner surface 154 of the screw cylinder135.

As shown in FIG. 20, the shaft insertion hole 150 of the sleeve Sv isscrew-connected to the screw cylinder 135. The shaft 134 is fixed to thesleeve Sv by the screw connection.

Retention of the sleeve Sv is achieved by the screw connection. As shownin FIG. 20, the lower side hole 152 of the sleeve Sv is screw-connectedto the connecting member 136. Withdrawal of the sleeve Sv is preventedby the screw connection. An axial force caused by the screw connectionbrings a hosel end face 158 into close contact with a bump surface 160of the sleeve Sv. In order to collateralize the axial force, a clearanceK1 exists between a tip of the connecting member 136 and a bottomsurface of the lower side hole 152 in a state where the screw connectionis completed (see FIG. 20).

In the embodiment, a first sleeve Sv1 and a second sleeve Sv2 areprepared as the sleeve Sv (see FIG. 19). The sleeve Sv1 and the sleeveSv2 are mutually changeable. As described above, this is because thesleeve Sv is detachably mounted to the shaft 134 (screw cylinder 135) bythe screw mechanism.

FIG. 22 is a cross sectional view of the first sleeve Sv1. As shown inFIG. 22, an axis line h1 of the shaft insertion hole 150 is inclined toan axis line z1 of the sleeve Sv. The inclination angle θ1 is a maximumvalue of an angle between the axis line h1 and the axis line z1. Theaxis line z1 of the sleeve Sv is substantially equal to an axis line ofthe hosel hole 142.

FIG. 23 is a cross sectional view of the second sleeve Sv2. As shown inFIG. 23, the axis line h1 of the shaft insertion hole 150 is notinclined to the axis line z1 of the sleeve Sv. The axis line h1 of theshaft insertion hole 150 coincides with the axis line z1 of the sleeveSv.

Although not shown in the drawings, other sleeve Sv having aninclination angle 82 different from the inclination angle θ1 may beused.

Variation of the sleeve Sv is not restricted to the inclination angle ofthe shaft insertion hole 150. For example, other sleeve Sv in which aposition of the shaft insertion hole 150 is changed may be also used.For example, other sleeve Sv in which the shaft insertion hole 150 ofthe second sleeve Sv2 is moved in parallel may be used. In this case,although the axis line z1 is parallel to the axis line h1, the axis linez1 does not coincide with the axis line h1.

The adjusting mechanism M7 of the embodiment is a sleeve changingmechanism. In the adjusting mechanism M7, one or more specificationsselected from a loft angle, a lie angle, and a face angle are adjustedby changing the sleeve Sv.

Examples of specifications capable of being adjusted by the adjustingmechanism M7 include a face progression, a lie angle, a loft angle, aface angle, a swingweight, a club length, a position of a center ofgravity of a club, a frequency of the club, a moment of inertia of theclub, a flex point of a shaft, a torque of the shaft, flexural rigidityof the shaft, torsional rigidity of the shaft, a shaft weight, weightdistribution of the shaft, a position of a center of gravity of theshaft, and a length of the shaft.

Examples of adjustments of the specifications by the adjusting mechanismM7 include the following adjustments:

(adjustment 7 a) although a lie angle is changed, a loft angle and aface angle are not substantially varied;

(adjustment 7 b) although a loft angle and a face angle are changed, alie angle is not substantially varied;

(adjustment 7 c) although a club length is changed, a loft angle, a faceangle, and a lie angle are not substantially varied;

(adjustment 7 d) although a flex point of a shaft is changed, a loftangle, a face angle, and a lie angle are not substantially varied;

(adjustment 7 e) although a face progression is changed, a loft angle, aface angle, and a lie angle are not substantially varied; and

(adjustment 7 f) although a distance of a center of gravity (a distancebetween a shaft axis line and a center of gravity of a head) is changed,a loft angle, a face angle, and a lie angle are not substantiallyvaried.

When the inclination angle θ1 of the sleeve Sv is 0 degree, the shaftcan be changed without varying the loft angle, the lie angle, and theface angle.

A plurality of sleeves Sv in which the inclination angle θ1 is 0 degreeand positions of the shaft insertion holes 150 are different from eachother may be prepared. In this case, the axis line of the shaftinsertion hole 150 can be moved in parallel by changing the sleeve Sv.In this case, the adjustment 7 e and the adjustment 7 f are possible.

FIG. 25 is an exploded perspective view of a head 170 used for a golfclub according to other adjusting mechanism. FIG. 26 is a crosssectional view of the head 170. Although not shown in the drawings, thegolf club is provided with the head 170, and a shaft, and a grip. Thehead 170 is a wood type golf club head.

As described later, the head 170 has an adjusting mechanism M8.Preferably, the golf club having the head 170 is further provided withother adjusting mechanism independent of the adjusting mechanism M8.

The head 170 has a front member 172, a back member 174, and a connectingmember 176. The front member 172 is connected to the back member 174 bythe connecting member 176. The front member 172 is connected to the backmember 174 in a state where no gap substantially exists. The hollow head170 is completed by the connection.

The front member 172 has a face surface 178. The front member 172 hasthe whole face surface 178. Although not shown in the drawings, thefront member 172 has a screw hole into which the connecting member 176is screwed, and a thick part for forming the screw hole. The frontmember 172 has a hosel part 180. The hosel part 180 has a shaft hole182. Although illustration is omitted, face grooves are formed in theface surface 178.

A back part of the front member 172 has an opening. An extending part181 capable of supporting an edge part 179 of the back member 174 froman inner side is formed in an edge of the opening. The extending part181 facilitates position adjustment of the back member 174 to the frontmember 172.

Although not shown in the drawings, the back member 174 has a throughhole through which the connecting member 176 passes and a thick part forforming the through hole.

The connecting member 176 is a screw. The front member 172 is connectedto the back member 174 by the connecting member 176.

The head 170 has the adjusting mechanism M8. A structure of theadjusting mechanism M8 is similar to the above-mentioned adjustingmechanism M1. The adjusting mechanism M8 is a screwing mechanism. Theadjusting mechanism M8 can change the back member 174.

A changing back member E8 is shown with the head 170 in FIG. 24. Achanging back member E81 and other changing back member E82 are shown asthe changing back member E8 in FIG. 25. The changing back member E81 andthe changing back member E82 can be connected to the front member 172 bythe connecting member 176. A golf club with an adjusting functionincludes the head 170 and at least one changing back member E8.

For example, a head shape is changed by changing the back member 174 tothe changing back member E8. For example, a position of a center ofgravity is changed by changing the back member 174 to the changing backmember E8. For example, a head volume is changed by changing the backmember 174 to the changing back member E8. A coefficient of restitutionof a head to a ball can be varied by changing the back member 174 to thechanging back member E8.

Examples of adjustments of the specifications by the adjusting mechanismM8 include the following adjustments:

(adjustment 8 a) a head shape is changed, and a position of a center ofgravity of a head is not substantially varied;

(adjustment 8 b) a head volume is changed, and a position of a center ofgravity of a head is not substantially varied;

(adjustment 8 c) a position of a center of gravity is changed, and ahead shape is not varied;

(adjustment 8 d) a moment of inertia is changed, and a head shape is notvaried; and

(adjustment 8 e) two or more adjustments selected from a head shape, ahead volume, and a position of a center of gravity of a head, and amoment of inertia are changed.

It is preferable that a head weight is not varied in the adjustingmechanism M8 in respect of maintaining the swingweight.

Although the adjusting mechanism M8 is applied to the wood type golfclub, the adjusting mechanism M8 may be used also for other type golfclubs (iron type, utility type, and putter type golf clubs or the like).

FIG. 26 shows a vicinity of a grip of a golf club according to otheradjusting mechanism. The golf club has a head (not shown), a shaft 190,and a grip 192. The head is mounted to one end part of the shaft 190.The grip 192 is mounted to the other end part of the shaft 190.

As described later, the golf club has an adjusting mechanism M9.Preferably, the golf club has other adjusting mechanism independent ofthe adjusting mechanism M9.

FIG. 27 is a cross sectional view of FIG. 26. FIG. 28 is a crosssectional view of a golf club taken along line F28-F28 of FIG. 27.

As shown in FIGS. 27 and 28, the shaft 190 is tube-shaped. The inside ofthe shaft 190 is a cavity.

The grip 192 has an inner side grip member 194 and an outer side gripmember 196. The inner side grip member 194 has a cylindrical shaftinsertion part 198. As shown in FIGS. 27 and 28, the shaft 190 isinserted into the shaft insertion part 198.

The inner side grip member 194 has an end part 200. An end face 202 ofthe shaft 190 abuts on the end part 200. A through hole 203 is formed ina center of the end part 200.

The outer side grip member 196 has a first division body 204 and asecond division body 206. The first division body 204 issemitube-shaped. The second division body 206 is also semitube-shaped.The tubular outer side grip member 196 is formed by the first divisionbody 204 and the second division body 206. As shown in FIG. 28, a bumppart 210 is formed in an edge of the first division body 204. As shownin FIG. 28, a bump part 212 is formed in an edge of the second divisionbody 206. A shape of the second division body 206 is the same as that ofthe first division body 204 except for a shape of the bump part.

In the outer side grip member 196, the bump part 210 of the firstdivision body 204 abuts on the bump part 212 of the second division body206. The bump part 210 is in mesh with the bump part 212. The outer sidegrip member 196 has an overlapping part in which the first division body204 overlaps the second division body 206. The bump part 210 and thebump part 212 form the overlapping part in which the first division body204 overlaps the second division body 206. A thickness of the outer sidegrip member 196 is set constant in the whole circumference of thecircumferential direction, including the overlapping part. In the outerside grip member 196, no gap exists in a portion in which the firstdivision body 204 abuts on the second division body 206. The cylindricalouter side grip member 196 is formed by a combination of the firstdivision body 204 and the second division body 206.

An outer surface 214 of the shaft insertion part 198 is covered with theouter side grip member 196. At least a part of the outer surface 214 iscovered with the outer side grip member 196. Preferably, the whole outersurface 214 is covered with the outer side grip member 196.

An inner surface 216 of the outer side grip member 196 includes an innersurface 218 of the first division body 204 and an inner surface 220 ofthe second division body 206. The inner surface 218 of the firstdivision body 204 is applied to the outer surface 214 of the shaftinsertion part 198. The inner surface 220 of the second division body206 is also applied to the outer surface 214 of the shaft insertion part198.

As shown in FIG. 27, the inner side grip member 194 has a first annularpart 222 extending outside in the radial direction from a grip-end sideend of the shaft insertion part 198, and a first cylindrical part 224extending to a head side from a radial outer side edge of the firstannular part 222. The first annular part 222 is a single annularportion. The first cylindrical part 224 is a single cylindrical portion.A first concave part 226 having the first annular part 222 formed as abottom is formed by the first annular part 222 and the first cylindricalpart 224.

As shown in FIG. 27, the inner side grip member 194 has a second annularpart 228 extending outside in the radial direction from a head side endof the shaft insertion part 198, and a second cylindrical part 230extending to a grip end side from a radial outer side edge of the secondannular part 228. The second annular part 228 is a single annularportion. The second cylindrical part 230 is a single cylindricalportion. A second concave part 232 having the second cylindrical part230 formed as a bottom is formed by the second annular part 228 and thesecond cylindrical part 230.

As shown in FIG. 27, the outer side grip member 196 has a grip-end sideend 234. Each of the first division body 204 and the second divisionbody 206 has the grip-end side end 234. The grip-end side end 234 isinserted into the first concave part 226. The grip-end side end 234 iscovered with the first cylindrical part 224. The grip-end side end 234is protected by the first cylindrical part 224. Since the grip-end sideend 234 is not exposed to the outside, the grip-end side end 234 ishardly turned up. Therefore, the first division body 204 and the seconddivision body 206 are hardly peeled off.

The outer side grip member 196 has a head side end 236. Each of thefirst division body 204 and the second division body 206 has the headside end 236. The head side end 236 is inserted into the second concavepart 232. The head side end 236 is covered with the second cylindricalpart 230. The head side end 236 is protected by the second cylindricalpart 230. Since the head side end 236 is not exposed to the outside, thehead side end 236 is hardly turned up. Therefore, the first divisionbody 204 and the second division body 206 are hardly peeled off.

The whole inner side grip member 194 is integrally formed. The firstannular part 222 and the first cylindrical part 224 are integrated withthe shaft insertion part 198. The second annular part 228 and the secondcylindrical part 230 are integrated with the shaft insertion part 198.

An inner circumferential surface 238 of the inner side grip member 194is bonded to an outer surface 240 of the shaft 190 by a double-sticktape. The inner side grip member 194 is mounted to the shaft 190 in thesame way as a general grip.

The inner surface 216 of the outer side grip member 196 is bonded to theouter surface 214 of the shaft insertion part 198 by a double-sticktape. In other words, the inner surface 218 of the first division body204 is bonded to the outer surface 214 by a double-stick tape, and theinner surface 220 of the second division body 206 is bonded to the outersurface 214 by a double-stick tape.

For example, a procedure for applying the outer side grip member 196 tothe shaft insertion part 198 of the inner side grip member 194 is asfollows:

(1 b) A double-stick tape is applied to the inner surface 218 of thefirst division body 204. A double-stick tape is applied to the innersurface 220 of the second division body 206;

(2 b) Any one of the first division body 204 and the second divisionbody 206 is applied to the shaft insertion part 198; and

(3 b) The other of the first division body 204 and the second divisionbody 206 is applied to shaft insertion part 198. At this time, the bumppart 210 is meshed with the bump part 212.

In the steps (2 b) and (3 b), the grip-end side end 234 is inserted intothe first concave part 226, and the head side end 236 is inserted intothe second concave part 232. The grip-end side end 234 is inserted intothe first concave part 226 while the first cylindrical part 224 isturned up. The head side end 236 is inserted into the second concavepart 232 while the second cylindrical part 230 is turned up.

A method for removing the first division body 204 is as follows. Thefirst division body 204 is removed by turning up the first cylindricalpart 224 or the second cylindrical part 230, and pulling the grip-endside end 234 or the head side end 236. A method for removing the seconddivision body 206 is the same as that of the first division body 204.Thus, the first division body 204 and the second division body 206 areeasily removed. The first division body 204 and the second division body206 are changeable.

The adjusting mechanism M9 is a changing mechanism for the outer sidegrip member. In the adjusting mechanism M9, a position of a center ofgravity of the club and a swingweight can be adjusted by changing theouter side grip member to the division bodies 204 and 206 havingdifferent weights in relation to each other. A grip weight can bechanged without varying a grip outer diameter by changing specificgravity of the division bodies 204 and 206. An outer diameter of thegrip 192 is changed by changing thicknesses of the division bodies 204and 206.

A material of the inner side grip member 194 is not restricted.Preferably, the material of the inner side grip member 194 is rubber.Examples of the rubber include crude rubber (specific gravity: 0.91 to0.93), styrene-butadiene rubber (specific gravity: 0.92 to 0.97), EPDM(specific gravity: 0.86 to 0.87), isoprene rubber (0.92 to 0.93), and amixture thereof. In respect of formability, ethylene-propylene dienerubber (EPDM) and styrene-butadiene rubber (SBR) are preferable. Whenthe inner side grip member 194 is rubber, the first cylindrical part 224and the second cylindrical part 230 can be turned up.

A material of the outer side grip member 196 is not restricted.Preferably, the material of the outer side grip member 196 is rubber.Examples of the rubber include crude rubber (specific gravity: 0.91 to0.93), styrene-butadiene rubber (specific gravity: 0.92 to 0.97), EPDM(specific gravity: 0.86 to 0.87), isoprene rubber (0.92 to 0.93), and amixture thereof. In respect of formability, ethylene-propylene dienerubber (EPDM) and styrene-butadiene rubber (SBR) are preferable. Inrespect of facilitating weight adjustment, rubber blended with a metalpowder having specific gravity equal to or greater than 10 ispreferable, and rubber blended with a metal powder having specificgravity equal to or greater than 15 is more preferable. Examples of themetal powder include a tungsten alloy powder.

Examples of adjustments of the specifications by the adjusting mechanismM9 include the following adjustments:

(adjustment 9 a) a thickness of a grip (grip outer diameter) is changed,and a swingweight is not substantially varied;

(adjustment 9 b) a thickness of a grip is changed, and a swingweight isalso changed;

(adjustment 9 c) a grip weight and a swingweight are changed, and athickness of a grip is not substantially varied; and

(adjustment 9 d) a grip weight and a swingweight are changed, and athickness of a grip is also changed.

FIG. 29 shows a vicinity of a grip end of a golf club provided with anadjusting mechanism M10 according to other embodiment. The golf club hasa head (not shown), a shaft 250, and a grip 252. The head is mounted toone end part of the shaft 250. The grip 252 is mounted to the other endpart of the shaft 250.

Preferably, the golf club is further provided with other adjustingmechanism independent of the adjusting mechanism M10.

Although a groove is formed in an outer surface (grip grasping surface)of the grip 252, the description of the groove is omitted in FIGS. 29 to32.

FIG. 30 is a cross sectional view of FIG. 29. FIG. 31 is an explodedview of FIG. 29.

The grip 252 has a grip body 252 a and two extending members 252 b. Thetwo extending members 252 b are mounted to a back end of the grip body252 a.

The grip body 252 a is fixed to a back end part of the shaft 250 by adouble-stick tape. A bonding method using the double-stick tape is thesame as a usual grip bonding method.

The first extending member 252 b is mounted to the back end of the gripbody 252 a. The second extending member 252 b is mounted to a back endof the first extending member 252 b.

An outer surface 252 a 1 of the grip body 252 a is substantiallysteplessly connected to an outer surface 252 b 1 of the extending member252 b. Furthermore, the outer surfaces 252 b 1 of the extending members252 b are substantially steplessly connected to each other. A graspingsurface 252m is formed by the outer surface 252 a 1 and the two outersurfaces 252 b 1.

The grip body 252 a has a rubber part g3 and a hard base h3. A materialof the rubber part g3 is rubber.

The hard base h3 is provided medially in the rubber part g3. The hardbase h3 is covered with the rubber part g3. The outer surface 252 a 1 ofthe grip body 252 a is an outer surface of the rubber part g3.

As shown in FIGS. 30 and 31, the hard base h3 has a screw hole sc3. Thehard base h3 has a cylinder part h31 and a bottom face part h32. Aninner surface of the cylinder part h31 is the screw hole sc3. The screwhole sc3 is opened upward.

The hard base h3 is fixed to the rubber part g3. The fixing method isnot restricted, and for example, is bonding using an adhesive.

The first extending member 252 b is located between the grip body 252 aand the second extending member 252 b. The first extending member 252 bhas a rubber part g4 and a hard connector h4. A material of the rubberpart g4 is rubber. An upper part of the hard connector h4 is coveredwith the rubber part g4.

The hard connector h4 is provided medially in the rubber part g4. Theouter surface 252 b 1 of the extending member 252 b is an outer surfaceof the rubber part g4.

The hard connector h4 has a cylindrical part h41 and a columnar part h42(see FIG. 30). An inner surface of the cylindrical part h41 is a screwhole sc4 (female screw). An outer surface of the columnar part h42 is amale screw. The cylindrical part h41 is disposed coaxially with thecolumnar part h42. The columnar part h42 has an exposed part ex2 exposedfrom the rubber part g4 (see FIG. 31). At least a part of the columnarpart h42 is the exposed part ex2. The exposed part ex2 protrudesdownward.

The columnar part h42 (male screw) is screwed into the screw hole sc3(female screw) of the grip body 252 a for connection between the firstextending member 252 b and the grip body 252 a. The columnar part h42 ofthe second extending member 252 b is screwed into the screw hole sc4 ofthe first extending member 252 b for connection between the extendingmembers 252 b.

All the extending members 252 b are common. The screw hole sc3 issimilar to the screw hole sc4.

An axial length of the exposed part ex2 is shorter than that of thescrew hole sc3. Therefore, a clearance K1 exists between the bottom facepart h32 and the columnar part h42 in a state where the grip body 252 ais connected to the extending member 252 b (see FIG. 30). The clearanceK1 prevents a gap from occurring in a boundary between the outer surface252 a 1 of the grip body 252 a and the outer surface 252 b 1 of theextending member 252 b.

The axial length of the exposed part ex2 is shorter than that of thescrew hole sc4. Therefore, a clearance K2 exists between an end face ofthe columnar part h42 and a bottom surface of the cylindrical part h41in a state where the extending members 252 b are connected to each other(see FIG. 30). The clearance K2 prevents a gap from occurring in aboundary between the outer surfaces 252 b 1 of the extending members 252b.

The second extending member 252 b is located on a grip back end siderather than the first extending member 252 b. The second extendingmember 252 b is a backmost extending member 252 b.

The second extending member 252 b is the same as the above-mentionedfirst extending member 252 b. Therefore, the description of the secondextending member 252 b is omitted.

Thus, in the embodiment, the grip body 252 a can be joined to theextending member 252 b by screw connection. Furthermore, the extendingmembers 252 b can be joined to each other by screw connection.

In the embodiment, the extending member 252 b is detachably mounted. Theextending member 252 b is removed by rotating the extending member 252 band releasing the screw connection. A grip length can be adjusted bymounting/demounting the extending member 252 b.

In the embodiment, the case where the number of the extending members252 b is 2 is shown. The grip length can be further changed by changingthe number of the extending members 252 b. The grip length can beshortened when the number of the extending members 252 b is 0. Thenumber of the extending members 252 b may be 1.

The number of the extending members 252 b may be equal to or greaterthan 3. Since a joining structure of the extending members 252 b is thesame, the number of the extending members 252 b to be joined can befreely selected.

Thus, the adjusting mechanism M10 according to the embodiment is a griplength adjusting mechanism. The adjusting mechanism M10 is also a clublength adjusting mechanism.

FIG. 32 is an exploded view of a grip 260 according to other embodimentusing the adjusting mechanism M10. The grip 260 has a grip body 252 a,an extending member 252 b, and an extending member 260 b. The grip body252 a is used for the above-mentioned grip 252. The extending member 252b is also used for the above-mentioned grip 252.

The extending member 260 b has a rubber part g5 and a hard connector h4.The hard connector h4 of the extending member 260 b is the same as thatof the above-mentioned extending member 252 b. A difference between theextending member 252 b and the extending member 260 b is only a lengthof the rubber part.

A length of a rubber part g4 of the extending member 252 b is shown by adouble pointed arrow L1 in FIG. 32. A length of a rubber part g5 of theextending member 260 b is shown by a double pointed arrow L2 in FIG. 32.The length L1 is different from the length L2. In the embodiment, alength of the grip 260 can be adjusted by selecting any one of theextending members 252 b and 260 b.

A material of the hard base is harder than that of a grip graspingsurface. Certainty of the connection and rigidity of the inner part ofthe grip can be improved by using the hard base. A material of the hardbase is preferably a metal or a resin, and more preferably the metal.Examples of the resin include a thermoplastic resin and a carbon fiberreinforced resin. In respect of processability, preferable examples ofthe resin include nylon, polyether block amide copolymer (PEBAX), andpolycarbonate. Examples of the metal include stainless steel, analuminium alloy, and a titanium alloy. In respect of a swingweight, ahigh specific gravity metal (specific gravity: equal to or greater than12) such as tungsten and a tungsten alloy can be also used.

A material of the hard connector is harder than that of a grip graspingsurface. Certainty of the connection and rigidity of the inner part ofthe grip can be improved by using the hard connector. A material of thehard connector is preferably a metal or a resin, and more preferably themetal. Examples of the resin include a thermoplastic resin and a carbonfiber reinforced resin. In respect of processability, preferableexamples of the resin include nylon, polyether block amide copolymer(PEBAX), and polycarbonate. Examples of the metal include stainlesssteel, an aluminium alloy, and a titanium alloy. In respect of aswingweight, a high specific gravity metal (specific gravity: equal toor greater than 12) such as tungsten and a tungsten alloy can be alsoused.

The rubber which is a material of the rubber part is not restricted. Therubber is preferably a rubber elastic body made of vulcanized rubber orthe like. It should be understood that a thermoplastic elastomer is alsoincluded in the rubber. In respect of low slidability or the like, cruderubber (specific gravity: 0.91 to 0.93), styrene-butadiene rubber(specific gravity: 0.92 to 0.97), EPDM (specific gravity: 0.86 to 0.87),isoprene rubber (specific gravity: 0.92 to 0.93), and a mixture thereofare preferable.

Examples of specifications capable of being adjusted by the adjustingmechanism M10 include a club length, a position of a center of gravityof a club, a frequency of the club, a moment of inertia of the club, agrip weight, a position of a center of gravity of a grip, and a griplength.

Examples of adjustments of the specifications by the adjusting mechanismM10 include the following adjustments:

(adjustment 10 a) a grip length and a club length are changed, and aswingweight is also changed; and

(adjustment 10 b) a grip length and a club length are changed, and aswingweight is not substantially varied.

The club length is extended by mounting the extending member. Theextension of the club length increases the swingweight. On the otherhand, an effect of so-called counter balance is caused by mounting theextending member. The counter balance decreases the swingweight. Thesetoff of both the club length and the swingweight can be promoted bysetting a weight and length of the extending member. The promotion cansuppress increase of the swingweight while increasing the club length.Furthermore, variation of the swingweight can be substantiallyeliminated while increasing the club length.

In all the specifications described in the present application, the term“is not substantially varied” means an amount of variation of less than10%. The term “is not substantially varied” for the swingweight meansvariation equal to or less than ±1 point. The swingweight is a 14 inchform. The swingweight is also referred to as swing balance.

FIG. 33 is an exploded perspective view of a head 268. FIG. 34 is a viewof the head 268, as viewed from a crown side. The head 268 is providedwith an adjusting mechanism M11 in addition to the above-mentionedadjusting mechanism M1. Although not shown in the drawings, a golf clubprovided with the head 268 is provided with the head 268, a shaft, and agrip. The head 268 is a wood type golf club head.

In the embodiment, the adjusting mechanism M1 is used as a loft angleadjusting mechanism. On the other hand, the adjusting mechanism M11 isused as a face angle adjusting mechanism.

A constitution of the head 268 is the same as that of theabove-mentioned head 2 except for existence of the adjustingintermediate member 270. The same portions of the head 268 as those ofthe head 2 are designated by the same reference numerals as those of thehead 2, and the repeated description is omitted.

The adjusting mechanism M11 has the adjusting intermediate member 270and a changing adjusting intermediate member (not shown). The adjustingintermediate member 270 is disposed between the front member 4 and theback member 6. The front member 4, the adjusting intermediate member270, and the back member 6 are connected to each other in a state whereno gap substantially exists. The adjusting intermediate member 270 isfixed with the adjusting intermediate member 270 sandwiched between thefront member 4 and the back member 6. The fixation is achieved by screwconnection of the connecting member 8.

The adjusting intermediate member 270 is a ring-shaped member. Theadjusting intermediate member 270 has a protruding part 272 (see FIG.33). The protruding part 272 protrudes toward the front member 4. Theprotruding part 272 facilitates position adjustment of the adjustingintermediate member 270 and the front member 4.

A face angle can be adjusted by varying a plane shape (see FIG. 34) ofthe adjusting intermediate member 270. The face angle can be adjusted bychanging the adjusting intermediate member 270 to other adjustingintermediate member which is not shown.

Thus, the head 268 has the plurality of (two) adjusting mechanisms M1and M11. The plurality of adjusting mechanisms M1 and M11 can beadjusted independently of each other. In the head 268, the loft angleand the face angle can be adjusted independently of each other.

Examples of specifications capable of being adjusted by the adjustingmechanism M11 include a face angle and a loft angle. The face angle andthe loft angle can be adjusted by only the adjusting mechanism M11without using the adjusting mechanism M1.

Examples of adjustments of the specifications by the adjusting mechanismM11 include the following adjustments:

(adjustment 11 a) a face angle is changed, and a loft angle is alsovaried;

(adjustment 11 b) a face angle is changed, and a loft angle is notsubstantially varied; and

(adjustment 11 c) a loft angle is changed, and a face angle is notsubstantially varied.

FIG. 35 is an exploded perspective view of a head 280 provided with anadjusting mechanism M12. Although not shown in the drawings, a golf clubprovided with the head 280 is provided with the head 280, a shaft, and agrip. The head 280 is a wood type golf club head.

The head 280 has a front member 282, a back member 284, and a connectingmember 8. The front member 282 is connected to the back member 284 bythe connecting member 8. The front member 282 is connected to the backmember 284 in a state where no gap substantially exists.

The front member 282 has a face surface 286. The front member 282 hasthe whole face surface 286. Although not shown in the drawings, thefront member 282 has a screw hole into which the connecting member 8 isscrewed. The front member 282 further has a thick part 288 for formingthe screw hole. Two thick parts 288 are provided at two positions.

The front member 282 has a plate-shaped face part 285, an upper sidebackward extending part 287, and a lower side backward extending part289. Both the two thick parts 288 are provided in the lower sidebackward extending part 289.

The front member 282 may not have the upper side backward extending part287 and the lower side backward extending part 289. That is, the wholefront member 282 may be plate-shaped. In this case, the thick part 288can be eliminated. In this case, the screw hole can be formed in theplate-shaped front member 282.

The back member 284 has a hosel part 290. The hosel part 290 has a shafthole 292. The back member 284 has a through hole 294 through which theconnecting member 8 passes and a thick part 296 for forming the throughhole 294. The thick part 296 is formed on each of the toe side and heelside of a sole of the head 280.

The back member 284 has a protruding part 298. In the embodiment, aplurality of (two) protruding parts 298 are provided. The protrudingparts 298 protrude forward from an opening part of the back member 284.The protruding parts 298 facilitate position adjustment of the frontmember 282. The protruding parts 298 facilitate screwing between thefront member 282 and the back member 284.

The connecting member 8 is a screw. The front member 282 is connected tothe back member 284 by the connecting member 8. The protruding parts 298improve certainty of the connection.

The head 2 has the adjusting mechanism M12. The adjusting mechanism M12is similar to the above-mentioned adjusting mechanism M1. A maindifference between the adjusting mechanism M12 and the adjustingmechanism M1 is a shape of the front member. The front member 282 has ashape formed by cutting a toe portion and heel portion of theabove-mentioned front member 4 (see FIG. 2). The front member 282 doesnot close the whole opening part of the back member 284. A hollow partof the head 280 is opened to the outside on the toe side of the frontmember 282. Furthermore, the hollow part of the head 280 is opened tothe outside on the heel side of the front member 282.

The adjusting mechanism M12 can change the front member 282. Forexample, a loft angle (real loft angle) is changed by changing the frontmember 282. For example, a face angle is changed by changing the frontmember 282.

Examples of specifications capable of being adjusted by the adjustingmechanism M12 include a loft angle, a face angle, a face area, and aface progression. Each of these specifications can be independentlyadjusted by the adjusting mechanism M12. Furthermore, a coefficient ofrestitution of the head to a ball, and a friction coefficient of thehead to the ball can be adjusted by the adjusting mechanism M12. Thecoefficient of restitution of the head to the ball can be adjusted by,for example, changing the front member to a changing front member havingrigidity different from that of the front member. The frictioncoefficient of the head to the ball can be adjusted by, for example,changing the front member to a changing front member having a facesurface having surface roughness different from that of the frontmember.

In the adjusting mechanism M12, a shape of the front member issimplified as compared with the above-mentioned adjusting mechanism M1.A mold for the front member can be manufactured at low cost by thesimplification. The simplification of the shape reduces a manufacturecost of the front member.

Examples of adjustments of the specifications by the adjusting mechanismM12 include the following adjustments:

(adjustment 12 a) a loft angle is changed, and a face angle is notsubstantially varied;

(adjustment 12 b) a loft angle is changed, and a face angle is alsochanged;

(adjustment 12 c) a loft angle is not substantially changed, and a faceangle is changed;

(adjustment 12 d) a face area is changed, and a loft angle and a faceangle are not varied; and

(adjustment 12 e) a face progression is changed, and a loft angle and aface angle are not varied.

Although the adjusting mechanism M12 is applied to the wood type golfclub head, the adjusting mechanism M12 may be used also for other typegolf clubs (iron type, utility type, and putter type golf clubs or thelike).

FIG. 37 is a view of a golf club 310 having an adjusting mechanism M13,as viewed from a sole side. The club 310 has a head 312. The adjustingmechanism M13 is a modification example of the above-mentioned adjustingmechanism M4. The adjusting mechanism M13 can adjust a real loft anglein addition to a lie angle. Although the number of positions of theshaft axis line capable of being selected is 3 in the above-mentionedadjusting mechanism M4, the number of positions of the shaft axis linecapable of being selected is 5 in the adjusting mechanism M13.

A reference shaft axis line is represented by reference character LS1(see FIG. 37). A second shaft axis line is represented by referencecharacter LF1. A third shaft axis line is represented by referencecharacter LU1. A fourth shaft axis line is represented by referencecharacter LP1. A fifth shaft axis line is represented by referencecharacter LM1.

Although the number of the holding holes h1 is 3 in the above-mentionedadjusting mechanism M4, the number of the holding holes h1 is 5 in theadjusting mechanism M13. That is, the head 312 has five holding holesh1. In the embodiment, the head 312 has a first holding hole h11, asecond holding hole h12, a third holding hole h13, a fourth holding holeh14, and a fifth holding hole h15. A constitution of the golf club 310is the same as that of the above-mentioned adjusting mechanism M4 (golfclub 70) except that the five holding holes h1 are formed; a space issecured so that the positions of the five kinds of shaft axis lines areallowed; and five kinds of sleeve supporting members 80 (describedabove) are provided.

The lie angle can be adjusted to three kinds by the adjusting mechanismM13. The three kinds of lie angles are achieved by the reference shaftaxis line LS1, the second shaft axis line LF1, and the third shaft axisline LU1. Furthermore, in the adjusting mechanism M13, the real loftangle can be adjusted to three kinds. The three kinds of real loftangles are achieved by the reference shaft axis line LS1, the fourthshaft axis line LP1, and the fifth shaft axis line LM1. The real loftangle is increased in the fourth shaft axis line LP1 as compared withthe reference shaft axis line LS1. The real loft angle is decreased inthe fifth shaft axis line LM1 as compared with the reference shaft axisline LS1.

FIG. 38 is a perspective view of a head 320 having an adjustingmechanism M14. FIG. 39 is an exploded perspective view of the head 320.FIG. 40 is a cross sectional view of the head 320.

The head 320 has a front member 322 and a back member 324. As shown inFIGS. 39 and 40, the back member 324 has an engagement protruding part326. The engagement protruding part 326 has an engaging groove 328 andan inclined surface 330 (see an enlarged part of FIG. 40). Theengagement protruding part 326 is formed in each of crown part and asole part of the head 320 (see FIG. 40). On the other hand, the frontmember 322 has an inner extending part 332. The inner extending part 332is fitted into a groove 328 of the engagement protruding part 326. Thefront member 322 is connected to the back member 324 by engagementbetween the engagement protruding part 326 and the inner extending part332. In the connected state, the outer surface of the front member 322is almost smoothly continuous with the outer surface of the back member324.

The front member 322 is detachably mounted to the back member 324. Inthe case of mounting, the engagement protruding part 326 of the backmember 324 is press fitted into an opening part of the front member 322.In the press fitting, a tip of the inner extending part 332 can slide ona surface of the inclined surface 330. The sliding can facilitate thepress fitting. The crown part and sole part of the back member 324 arecompressed toward the inner side of the head in the case of pressfitting if needed.

In the case of removal, the crown part and sole part of the back member324 are compressed toward the inner side of the head, to releaseengagement between the engaging groove 328 and the inner extending part332. The front member 322 can be removed from the back member 324 by therelease. The adjusting mechanism M14 can change the back member 324.

Plastic deformation of the back member 324 is required formounting/demounting. In respect of facilitating the mounting/demounting,a material of the back member 324 may be fiber-reinforced plastic.

For example, a position of a center of gravity is changed by changingthe back member 324. For example, a head volume is changed by changingthe back member 324.

Examples of adjustments of the specifications by the adjusting mechanismM14 include the following adjustments:

(adjustment 14 a) a head shape is changed, and a position of a center ofgravity of a head is not substantially varied;

(adjustment 14 b) a head volume is changed, and a position of a centerof gravity of a head is not substantially varied;

(adjustment 14 c) a position of a center of gravity is changed, and ahead shape is not varied;

(adjustment 14 d) a moment of inertia is changed, and a head shape isnot varied; and

(adjustment 14 e) two or more selected from a head shape, a head volume,a position of a center of gravity of a head, and a moment of inertia arechanged.

It is preferable that a head weight is not varied in the adjustingmechanism M14 in respect of maintaining a swingweight.

Although the adjusting mechanism M14 is applied to the wood type golfclub, the adjusting mechanism M14 may be used also for other type golfclubs (iron type, utility type, and putter type golf clubs or the like).

FIG. 41 is a plan view of a head 340 having an adjusting mechanism M15.FIG. 42 is a cross sectional view taken along line F42-F42 of FIG. 41.FIG. 43 is a bottom view of the head 340. The head 340 has a frontmember 342, a back member 344, and a spacer 34 6. A crown part of thefront member 342 is rotatably joined to a crown part of the back member344. A hinge 348 is used for the joining.

The spacer 346 is interposed between the front member 342 and the backmember 344. The spacer 346 is located in the head 340. However, a bottomsurface of the spacer 346 is exposed to the outside. The bottom surfaceof the spacer 346 constitutes a part of a sole surface of the head 340.

The hinge 348 allows rotation of the front member 342 to the back member344. The rotation can adjust a real loft angle. On the other hand, whenthe head 340 is used, the rotation is fixed. The fixation is achieved bya screw member 350. The screw member 350 passes through the spacer 346,and connects the front member 342 to the back member 344.

A groove 352 opened downward and a protruding part 354 extendingdownward are formed in an edge of a lower end of the front member 342 (alower end of a face part). Similarly, a groove 352 opened downward and aprotruding part 354 extending downward are formed in an edge of a frontend of a sole part of the back member 344. On the other hand, a groove356 opened upward and a protruding part 358 extending upward are formedin a front edge of a lower surface of the spacer 346. Similarly, agroove 356 opened upward and a protruding part 358 extending upward areformed in a back edge of the lower surface of the spacer 346.

As shown in an enlarged part of FIG. 42, the protruding part 354 isfitted into the groove 356 in the back edge of the lower surface of thespacer 346, and the protruding part 358 is fitted into the groove 352.The protruding part 354 is fitted into the groove 356 also in the frontedge of the lower surface of the spacer 346, and the protruding part 358is fitted into the groove 352. Fixation of the spacer 346 is achieved bythese fittings.

A real loft angle can be varied by a thickness and shape of the spacer346. The real loft angle can be adjusted by changing the spacer 346.

[Specification]

In the present invention, the specification capable of being adjusted isnot restricted. Examples of the specification include a loft angle, alie angle, a face angle, a face area, a position of a center of gravityof a head, a swingweight, a club length, a position of a center ofgravity of a club, a frequency of the club, a club weight, a head shape,a head volume, a head weight, a flex of a shaft (shaft hardness), a flexpoint of a shaft, a torque of the shaft, flexural rigidity distributionof the shaft, torsional rigidity distribution of the shaft, a shaftweight, weight distribution of the shaft, a position of a center ofgravity of the shaft, a length of the shaft, a grip outer diameter, agrip weight, a position of a center of gravity of a grip, a grip length,a specification of a face groove, a face progression, a moment ofinertia of the head, a moment of inertia of the club, a coefficient ofrestitution of the head to a ball, and a friction coefficient of thehead to the ball.

In the present invention, at least two specifications can be adjustedindependently of each other. More preferably, all the specificationscapable of being adjusted can be adjusted independently of each other.

The specification includes a specification according to the head, aspecification according to the shaft, a specification according to thegrip, and a specification according to the whole club.

Examples of the specification according to the head include a loftangle, a lie angle, a face angle, a face area, a position of a center ofgravity of a head, a head shape, a head volume, a head weight, a faceprogression, a moment of inertia of the head, a coefficient ofrestitution of the head to a ball,and a friction coefficient of the headto the ball. Examples of the position of the center of gravity of thehead include a distance of a center of gravity (a distance between ashaft axis line and a center of gravity of the head), a depth of thecenter of gravity, and a sweet spot height besides an actual(three-dimensional) position of a center of gravity of the head.

Examples of the specification according to the shaft in thespecifications include a flex of a shaft, a flex point of a shaft, atorque of the shaft, flexural rigidity distribution of the shaft,torsional rigidity distribution of the shaft, a shaft weight, weightdistribution of the shaft, a position of a center of gravity of theshaft, and a length of the shaft.

Examples of the specification according to the grip in thespecifications include a grip outer diameter, a grip weight, a positionof a center of gravity of a grip, and a grip length.

Examples of the specification according to the whole club in thespecifications include a swingweight, a club length, a position of acenter of gravity of a club, a frequency of the club, a club weight, anda moment of inertia of the club.

An adjustment range of the specification is not restricted. In respectof a degree of freedom of adjustment, the adjustment range is preferablywider. In this respect, the adjustment range of the loft angle ispreferably equal to or greater than 2 degrees, preferably equal to orgreater than 3 degrees, and still more preferably equal to or greaterthan 4 degrees. The adjustment range of the face angle is preferablyequal to or greater than 2 degrees, more preferably equal to or greaterthan 3 degrees, and still more preferably equal to or greater than 4degrees. The adjustment range of the lie angle is preferably equal to orgreater than 1 degree, more preferably equal to or greater than 2degrees, and still more preferably equal to or greater than 3 degrees.The adjustment range of the distance of a center of gravity ispreferably equal to or greater than 5 mm, more preferably equal to orgreater than 10 mm, and still more preferably equal to or greater than15 mm. The adjustment range of the club length is preferably equal to orgreater than 1 inch, more preferably equal to or greater than 1.5inches, and still more preferably equal to or greater than 2 inches. Theadjustment range of the head volume is preferably equal to or greaterthan 10 cc, more preferably equal to or greater than 20 cc, and stillmore preferably equal to or greater than 30 cc. The adjustment range ofthe grip outer diameter is preferably equal to or greater than 0.5 mm,more preferably equal to or greater than 1 mm, and still more preferablyequal to or greater than 1.5 mm. The adjustment range of the swingweightis preferably equal to or greater than 1 point, more preferably equal toor greater than 2 points, and still more preferably equal to or greaterthan 3 points.

In respect of improving the degree of freedom of adjustment, anadjustment range in a specific specification is preferably equal to orgreater than a range corresponding to two-number clubs. The rangecorresponding to two-number clubs is as follows. The specificspecification is one or more selected from a loft angle, a lie angle, aclub length, and a club weight.

[Range Corresponding to Two-Number Clubs]

-   -   Loft angle: 6 degrees    -   Lie angle: 1 degree    -   Club length: 1 inch    -   Club weight: 14 g

[Adjusting Mechanism]

The golf club of the present invention has one or more adjustingmechanisms. The adjusting mechanism is not restricted. The adjustingmechanism can adjust the specification. One adjusting mechanism canadjust one or more specifications. One adjusting mechanism may be ableto adjust two or more specifications. Two or more specificationsadjusted by one adjusting mechanism may be adjusted so as to beinterlocked with each other, and may be independently adjusted withoutbeing interlocked with each other.

Preferably, the golf club has a plurality of adjusting mechanisms.Preferably, two or more specifications can be adjusted independently ofeach other by the plurality of adjusting mechanisms.

Preferably, the adjusting mechanism can adjust the specificationaccording to the head without changing the whole head. Preferably, theadjusting mechanism can adjust the specification according to the gripwithout changing the whole grip. Preferably, the adjusting mechanism canadjust the specification according to the shaft without changing thewhole shaft.

Examples of the adjusting mechanism include the adjusting mechanism M1,the adjusting mechanism M2, the adjusting mechanism M3, the adjustingmechanism M4, the adjusting mechanism M5, the adjusting mechanism M6,the adjusting mechanism M7, the adjusting mechanism M8, the adjustingmechanism M9, the adjusting mechanism M10, the adjusting mechanism M11,the adjusting mechanism M12, the adjusting mechanism M13, the adjustingmechanism M14, and the adjusting mechanism M15. The adjusting mechanismsdescribed in the above-mentioned Patent Documents can be also applied tothe present invention.

Examples of the golf club provided with a plurality of adjustingmechanisms include a golf club provided with two or more adjustingmechanisms selected from the adjusting mechanism M1, the adjustingmechanism M2, the adjusting mechanism M3, the adjusting mechanism M4,the adjusting mechanism M5, the adjusting mechanism M6, the adjustingmechanism M7, the adjusting mechanism M8, the adjusting mechanism M9,the adjusting mechanism M10, the adjusting mechanism M11, the adjustingmechanism M12, the adjusting mechanism M13, the adjusting mechanism M14,and the adjusting mechanism M15.

The adjusting mechanisms described in the embodiment can be independentfrom each other. That is, when the plurality of adjusting mechanisms isprovided in a single golf club, the plurality of adjusting mechanismscan function without being interlocked with each other. The independencebetween the adjusting mechanisms improves the degree of freedom ofadjustment.

Two or more adjusting mechanisms selected from the above-mentionedadjusting mechanisms M1 to M15 can be set in a single golf club. The twoor more adjusting mechanisms can be set in the single golf club withinthe technical level of a person skilled in the art except that it isparticularly difficult to provide the two or more adjusting mechanisms.

The head may have a plurality of adjusting mechanisms. In this case, thedegree of freedom of adjustment of the specification according to thehead is improved. The shaft may have a plurality of adjustingmechanisms. In this case, a degree of freedom of adjustment of thespecification according to the shaft is improved. The grip may have aplurality of adjusting mechanisms. In this case, a degree of freedom ofadjustment of the specification according to the grip is improved.

When a plurality of adjusting mechanisms independent of each other isprovided, the specification adjusted by one adjusting mechanism and thespecification adjusted by other adjusting mechanism can be adjustedindependently of each other. The independence between the specificationsimproves the degree of freedom of adjustability.

Even if the number of the adjusting mechanisms is 1, the plurality ofspecifications may be adjusted independently of each other. For example,the face angle and the loft angle can be independently adjusted in theadjusting mechanism M1. That is, in setting a direction of the facesurface of the front member 4, the loft angle can be also varied withoutvarying the face angle,and the face angle can be also varied withoutvarying the loft angle. In addition, the loft angle and the face anglecan be also varied independently of each other.

Preferably, the plurality of adjusting mechanisms is provided. Inrespect of the degree of freedom of adjustability When two or moreadjusting mechanisms are provided, at least two of the adjustingmechanisms can be preferably adjusted independently of each other. Forexample, in the case of a golf club having three adjusting mechanisms, afirst adjusting mechanism and a second adjusting mechanism can bepreferably adjusted independently of each other, and the first adjustingmechanism, the second adjusting mechanism, and a third adjustingmechanism can be preferably adjusted independently of each other. Thatis, when the two or more adjusting mechanisms are provided, all theadjusting mechanisms can be most preferably adjusted independently ofeach other.

In the embodiment shown in FIG. 17 of the above-mentioned US2006/0293115, the loft angle, the lie angle, and the face angle arevaried in relation to each other due to the circumferential position ofthe sleeve. In this case, the three specifications cannot be adjustedindependently of each other. The non-independence reduces the degree offreedom of adjustability. The present invention can solve the problem.

A material of the head (or the head body) is not restricted. Preferableexamples of the material include a titanium alloy, stainless steel, analuminium alloy, a magnesium alloy, carbon fiber reinforced plastic(CFRP), and a combination thereof. A manufacturing method of the head isnot restricted, and examples thereof include forging, casting, pressing,and a combination thereof. The head may be made of a plurality ofcombined materials. A structure of the head body is not restricted.

A material of the shaft is not restricted. Examples of the material ofthe shaft include carbon fiber reinforced plastic (CFRP) and a metal. Aso-called carbon shaft and steel shaft can be suitably used. A structureof the shaft is not restricted.

A material of the sleeve is not restricted. Preferable examples of thematerial include a titanium alloy, stainless steel, an aluminium alloy,a magnesium alloy, and a resin. It is preferable that the resin hasexcellent mechanical strength. For example, the resin is preferably aresin referred to as an engineering plastic or a super-engineeringplastic. As described above, the engaging member may be integrallyformed with the head body. In respect of a balance between strength andlightweight, for example, the aluminium alloy and the titanium alloy aremore suitable.

A material of the engaging member is not restricted. Preferable examplesof the material include a titanium alloy, stainless steel, an aluminiumalloy, a magnesium alloy, and a resin. It is preferable that the resinhas excellent mechanical strength. For example, the resin is preferablya resin referred to as an engineering plastic or a super-engineeringplastic. As described above, the engaging member may be integrallyformed with the head body.

A material of the connecting member (screw) is not restricted.Preferable examples of the material include a titanium alloy, stainlesssteel, an aluminium alloy, and a magnesium alloy.

A material of the sleeve supporting member 80 is not restricted.Preferable examples of the material include a titanium alloy, stainlesssteel, an aluminium alloy, and a magnesium alloy besides theabove-mentioned resin.

The specifications can be measured by known measuring devices. Examplesof the measuring devices for the loft angle, the lie angle, and the faceangle include a golf club head gauge manufactured by Sheng Feng IronEnterprise Co. Some typical specifications may be described in a productcatalog.

A combination of the specifications capable of being adjusted is notrestricted. The number of the specifications capable of being adjustedis not restricted. The number is preferably equal to or greater than 3,and more preferably equal to or greater than 4.

A golf club A having the adjusting mechanism capable of adjusting theloft angle and the adjusting mechanism capable of adjusting the distanceof a center of gravity is effective in a situation where a mistake ofpulling a ball using a short iron is apt to occur, for example. In thiscase, the mistake can be resolved by increasing the loft angle andlengthening the distance of a center of gravity. The golf club A iseffective in a situation where a mistake of opening a face of the shortiron is apt to occur, for example. In this case, the mistake can beresolved by increasing the loft angle and shortening the distance of acenter of gravity. In a condition where a wind is strong and a ball isapt to be pulled, adjustment for decreasing the loft angle andincreasing the distance of a center of gravity is effective.

A golf club B having the adjusting mechanism capable of adjusting theloft angle and the adjusting mechanism capable of adjusting the clublength is effective in increasing a flight distance. An example ofeffective adjustment in this case is adjustment for lengthening the clublength to increase the head speed and increasing the loft angle toincrease a launch angle. The golf club B is effective in improvingcontrollability. An example of effective adjustment in this case isadjustment for shortening the club length to decrease the flightdistance and increasing the loft angle to increase the launch angle. Inthis case, a ball having a high trajectory to tend to stop at a fallspot can be achieved. Since adjustment for decreasing the loft angle andlengthening the club length can achieve a low launch angle andimprovement in the head speed, the adjustment is effective in improvingthe total flight distance including a run. Since adjustment decreasingthe loft angle and shortening the club length can achieve a low launchangle and decrease in the head speed, the adjustment is effective whenthe run is desired to be increased by a low hit ball.

A golf club C having the adjusting mechanism capable of adjusting theloft angle and the adjusting mechanism capable of adjusting theswingweight is effective in improving controllability. As an example ofeffective adjustment in this case, the swingweight is increased tostabilize a swing, and the loft angle is increased to increase thelaunch angle. Alternatively, the swingweight is decreased to increasethe head speed, and the loft angle is increased to increase the launchangle. In this case, a ball having a high trajectory to tend to stop ata fall spot can be achieved. Since adjustment for decreasing the loftangle and increasing the swing balance can achieve a low launch angleand a stable (slow) swing, the adjustment is effective in obtaining alow trajectory having excellent directivity. Since adjustment fordecreasing the loft angle and decreasing the swing balance can achieve alow launch angle and improvement in a head speed, it is effective inincreasing a run by a low trajectory to increase the total flightdistance.

An impact force caused by hitting concentrates on the hosel part.Strength is required for the hosel part. Since a weight of the hoselpart is increased when the adjusting mechanism is located in the hoselpart, a degree of freedom of design of the center of gravity of the headis reduced. It is preferable that the hosel part has a light weight. Inrespect of strength of the hosel part and reduction in a weight of thehosel part, the following constitution (a) is preferable; the followingconstitution (b) is more preferable; and the following constitution (c)is still more preferable:

(a) the adjusting mechanism (1) or the adjusting mechanism (2) islocated at a place other than the hosel part;

(b) the adjusting mechanism (1) and the adjusting mechanism (2) arelocated at places other than the hosel part; and

(c) all the adjusting mechanisms are located at places other than thehosel part.

The adjusting mechanisms M3, M4, M7, and M13 are located in the hoselpart in the embodiments. The adjusting mechanisms M1, M2, M5, M6, M8,M9, M10, M11, M12, M14, and M15 are located at places other than thehosel part.

Examples in which the adjusting mechanism located at a place other thanthe hosel part is combined with the adjusting mechanism located in thehosel part include examples 2 to 11 to be described later. Examples inwhich the adjusting mechanisms located at places other than the hoselpart are combined with each other include examples 1 and 12 to 28 to bedescribed later.

Examples of the constitution (a) include the following constitutions(a1) to (a5):

(a1) the adjusting mechanism (1) or the adjusting mechanism (2) islocated in the grip;

(a2) the adjusting mechanism (1) or the adjusting mechanism (2) islocated in the shaft;

(a3) the adjusting mechanism (1) or the adjusting mechanism (2) islocated in the joined part between the shaft and the grip;

(a4) the adjusting mechanism (1) or the adjusting mechanism (2) islocated in the sole of the head; and

(a5) the adjusting mechanism (1) or the adjusting mechanism (2) islocated in the head other than the hosel part.

In respect of adjusting a mounting angle of the shaft to the head, theother of the adjusting mechanism (1) or the adjusting mechanism (2) maybe located in the hosel part in each of the constitutions (a1), (a2),(a3), (a4), and (a5).

Examples of the constitution (b) include the following constitutions(b1) to (b8):

(b1) the adjusting mechanism (1) and the adjusting mechanism (2) arelocated in the grip;

(b2) the adjusting mechanism (1) and the adjusting mechanism (2) arelocated in the shaft;

(b3) the adjusting mechanism (1) and the adjusting mechanism (2) arelocated in the head other than the hosel part;

(b4) the adjusting mechanism (1) and the adjusting mechanism (2) arelocated in the sole of the head;

(b5) the adjusting mechanism (1) is located in the shaft, and theadjusting mechanism (2) is located in the grip;

(b6) the adjusting mechanism (1) is located in the shaft, and theadjusting mechanism (2) is located in the head other than the hoselpart;

(b7) the adjusting mechanism (1) is located in the grip, and theadjusting mechanism (2) is located in the head other than the hoselpart; and

(b8) the adjusting mechanism (1) is located in the grip, and theadjusting mechanism (2) is located in the sole of the head.

The adjusting mechanism M1 is located in the head other than the hoselpart. The adjusting mechanism M2 is located in the head other than thehosel part. The adjusting mechanism M3 is located in the hosel part. Theadjusting mechanism M4 is located in the hosel part. The adjustingmechanism M5 is located in the head other than the hosel part, and islocated in the sole of the head. The adjusting mechanism M6 is locatedin the grip, and is located in the shaft. The adjusting mechanism M7 islocated in the hosel part. The adjusting mechanism M8 is located in thehead other than the hosel part. The adjusting mechanism M9 is located inthe grip. The adjusting mechanism M10 is located in the grip. Theadjusting mechanism M11 is located in the head other than the hoselpart. The adjusting mechanism M12 is located in the head other than thehosel part. The adjusting mechanism M13 is located in the hosel part.The adjusting mechanism M14 is located in the head other than the hoselpart. The adjusting mechanism M15 is located in the head other than thehosel part.

When the two adjusting mechanisms interfere with each other, themechanism becomes complicated. The complicated mechanism is apt to causea trouble. The complicated mechanism may require high dimensionalaccuracy. The high dimensional accuracy reduces productivity. In theserespects, it is preferable that the adjusting mechanism (1) and theadjusting mechanism (2) do not interfere with each other. The meaning ofthe term “interfere” is as follows. When at least one memberconstituting an adjusting mechanism A involves in an adjusting mechanismB, the adjusting mechanisms A and B are defined to interfere with eachother. When at least one member constituting the adjusting mechanism Binvolves in the adjusting mechanism A, the adjusting mechanisms A and Bare defined to interfere with each other. One example of theinterference is a case where a screw for fixing the adjusting mechanismA contributes also to fixation of the adjusting mechanism B, forexample.

The specification of the shaft can be adjusted by changing the shaft.However, a cost of the shaft is high. Golf players request desiredadjustment of other specifications without changing the shaft preferredby the golf players themselves. In these respects, it is preferable thatthe adjusting mechanism (1) and the adjusting mechanism (2) involve noshaft change. It is more preferable that all the adjusting mechanismsinvolve no shaft change.

On the other hand, a sleeve is preferably used in a golf club having achangeable shaft. The sleeve is used in the adjusting mechanisms M4 andM7, for example. As shown in the adjusting mechanism M4, the sleeve istypically bonded to the shaft. The shaft is detachably mounted to thehead by using the sleeve, to facilitate the change of the shaft. A largeimpact force from hitting acts on the sleeve. In respect of ensuringfixation of the sleeve, it is preferable that the sleeve is supported bysurface contact in the whole circumferential direction (360 degrees).The sleeve is supported by the surface contact in the wholecircumferential direction in the adjusting mechanism M4 and theadjusting mechanism M7. Of these, in the adjusting mechanism M4, thesleeve supporting member 80 is brought into surface contact with thesleeve 76 in the whole circumferential direction.

In a golf club set having the plurality of the golf clubs describedabove, advantages of the clubs are synergistically combined, and therebythe golf club set having excellent adjustability can be achieved.

As exemplified above, the golf club having the two or morespecifications capable of being adjusted independently enablesadjustments corresponding to situations such as course setting, weather,and a condition of a player. A combination of specifications other thanthe above description enables adjustments corresponding to varioussituations.

EXAMPLES

Hereinafter, the effects of the present invention will be clarified byexamples. However, the present invention should not be interpreted in alimited way based on the description of the examples. The followingadjusting mechanisms are the same as those described in theabove-mentioned embodiment unless particularly described.

Example 1

A head having the adjusting mechanism M1 (face angle adjustingmechanism) and the adjusting mechanism M5 (a head-center-of-gravityposition adjusting mechanism) was produced. A front member 4 and backmember 6 of the head were produced by a lost-wax precision casting usinga titanium alloy (Ti-6Al-4V). A material of a connecting member 8(screw) was a titanium alloy (Ti-6Al-4V). A screw hole into which aweight body 104 (screw) of the adjusting mechanism M5 was screwed wasformed in a sole of the back member 6, and was produced by NCprocessing. A shaft (carbon shaft) and a grip were mounted to the head,to obtain a golf club according to example 1. The golf club was a numberthree wood golf club.

Example 2

A golf club having the adjusting mechanism M1 (face angle adjustingmechanism), the adjusting mechanism M4 (lie angle adjusting mechanism),the adjusting mechanism M5 (a head-center-of-gravity position adjustingmechanism), and the adjusting mechanism M6 (swingweight adjustingmechanism) was produced. The adjusting mechanism M4 was added to a hoselpart of the back member of the example 1, and a grip with the adjustingmechanism M5 shown in FIG. 17 was mounted in place of the grip of theexample 1. A material of a sleeve 76 was an aluminium alloy. A materialof a sleeve supporting member 80 was an aluminium alloy. A golf club ofexample 2 was obtained in the same manner as in the example 1 as for therest.

Comparative Example 1

A head of comparative example 1 was obtained in the same manner as inthe example 1 except that the head did not have all the adjustingmechanisms. The head was obtained by welding a front member 4 to a backmember 6. The same shaft and grip as those of the example 1 were mountedto the head, to obtain a golf club according to the comparative example1.

Comparative Example 2

The same structure as that of the above-mentioned adjusting mechanism M7(see FIG. 20) was formed in the back member 6 of the example 1. The samefront member as that of the example 1 was welded to the back member, toobtain a head. The screw groove of the inner surface of the sleeve Sv inthe adjusting mechanism M7 was removed, to form a circumferentialsurface. The sleeve Sv was bonded to the tip part of the same shaft asthat of the example 1. That is, the shaft was directly bonded to theinner surface of the sleeve Sv without using the screw cylinder 135. Ashaft insertion hole was inclined to a hosel hole 142 as in theabove-mentioned sleeve Sv1 (to see FIG. 22). The inclination angle θ1(see FIG. 22) was set to 1.0 degree. A material of the sleeve Sv was analuminium alloy. A material of an engaging member 140 was a titaniumalloy (Ti-6Al-4V). Furthermore, the same grip as that of the example 1was mounted, to obtain a golf club according to comparative example 2.In the golf club, the shaft can be detachably mounted to the head by ascrew mechanism. In the golf club, a loft angle, a lie angle, and a faceangle are varied in relation to each other by a relative positionrelation in a circumferential direction between the sleeve Sv and thehosel hole.

An evaluation test was performed by tester's actual hitting using theseclubs. The tester had a driver head speed of about 40 m/s, and was aslicer (the tester was apt to slice a ball). Specifications andevaluation results of the examples and comparative examples are shown inthe following Table 1.

TABLE 1 Specifications and evaluation results of examples andcomparative examples Comparative Comparative Comparative example 1example 2-1 example 2-2 Example 1 Example 2 Loft angle (°) 16.5 17.515.5 16.5 17.5 Face angle (°) 3 5 1 5 5 Lie angle (°) 58.5 58 59 58.559.5 Distance of center of 35 35 35 33 33 gravity (mm) Club length(inch) 42.5 42.5 42.5 42.5 42.5 Balance D1 D1 D1 D1 D0 Ball initialspeed (m/s) 53 52.5 53 54 53 Launch angle (°) 20 23 17 20 23 Backspinamount 3200 3500 2800 3000 3300 (rpm) Side spin amount 1500 1000 2000500 200 (rpm) Flight distance (yard) 170 176 165 184 190 Directivity(yard) +25 +10 +40 +5 0

In “directivity” in Table 1 and each of the following Tables, “+” meansthat the direction is deviated to the right side from the targetdirection, and “−” means that the direction is deviated to the left sidefrom the target direction. In “side spin” in Table 1 and each of thefollowing Tables, a positive value means slice rotation, and a negativevalue means hook rotation.

The example 1 can be adjusted to the specification of the comparativeexample 1 shown in Table 1. The example 1 was adjusted to thespecification shown in Table 1, and an evaluation test thereof wasperformed.

The example 2 can be adjusted to the specification of the comparativeexample 1 shown in Table 1. The example 2 was adjusted to thespecification shown in Table 1, and an evaluation test thereof wasperformed.

A club having a state of comparative example 2-1 was produced using thecomparative example 2, and an evaluation test thereof was performed.Next, a club having a state of comparative example 2-2 was produced byvarying a relative position relation in a circumferential directionbetween a sleeve Sv (shaft) and a hosel hole, and an evaluation testthereof was performed.

As shown in Table 1, since a loft angle, a lie angle, and a face angleare varied in relation to each other in the comparative example 2, theadjustment was insufficient. Therefore, the slice was insufficientlyresolved, and the flight distance was also relatively short. Theexamples 1 and 2 had excellent adjustability, and provided good resultsin resolution of slice and a flight distance.

Example 3

A head having the adjusting mechanism M1 (face angle adjustingmechanism) and the adjusting mechanism M4 (lie angle adjustingmechanism) was produced. A front member 4 and back member 6 of the headwere produced by a lost-wax precision casting using a titanium alloy(Ti-6Al-4V). The adjusting mechanism M4 was provided in a hosel part ofthe back member 6. A shaft (carbon shaft) and a grip were mounted to thehead, to obtain a golf club according to example 3. The golf club was anumber three wood golf club.

Comparative Example 3

A head of comparative example 3 was obtained in the same manner as inthe comparative example 1 except that the specification was changed tothe specification of Table 2. The same shaft and grip as those of theexample 1 were mounted to the head, to obtain a golf club according tocomparative example 3.

Comparative Example 4

A head of comparative example 4 was obtained in the same manner as inthe comparative example 2 except that the specification was changed tothe specification of Table 2. In the golf club, a shaft is detachablymounted to a head by a screw mechanism. In the golf club, a loft angle,a lie angle, and a face angle are varied in relation to each other by arelative position relation in a circumferential direction between asleeve Sv and a hosel hole.

An evaluation test was performed by tester's actual hitting using theseclubs. The tester had a driver head speed of about 40 m/s, and was aslicer (the tester was apt to slice a ball). Specifications andevaluation results of the examples and comparative examples are shown inthe following Table 2.

TABLE 2 Specifications and evaluation results of examples andcomparative examples Comparative Comparative Comparative Example Exampleexample 3 example 4-1 example 4-2 3-1 3-2 Loft angle (°) 16.5 17.5 15.516.5 16.5 Face angle (°) 3 5 1 5 6 Lie angle (°) 58.5 58 59 59 59Distance of 30 30 30 30 30 center of gravity (mm) Club length (inch) 4242 42 42 42 Balance D1 D1 D1 D1 D1 Ball initial speed 53 52.5 53 54 54(m/s) Launch angle (°) 20 23 17 20 20 Backspin amount 3200 3500 30003000 3000 (rpm) Side spin amount 1500 1000 2000 500 200 (rpm) Flightdistance 170 160 165 184 190 (yard) Directivity (yard) +25 +10 +40 +5 0Variable Face Face mechanism angle angle Lie angle Lie angle

The golf club of the example 3 was adjusted to a specification ofexample 3-1 shown in Table 2 using the adjusting mechanism, and wasevaluated. Furthermore, the golf club of the example 3 was adjusted to aspecification of example 3-2 shown in Table 2 using the adjustingmechanism, and was evaluated.

A club having a state of comparative example 4-1 was produced using thecomparative example 4, and an evaluation test thereof was performed.Next, a club having a state of comparative example 4-2 was produced byvarying a relative position relation in a circumferential directionbetween a sleeve Sv (shaft) and a hosel hole, and an evaluation testthereof was performed.

As shown in Table 2, since a loft angle, a lie angle, and a face angleare varied in relation to each other in the comparative example 4, theadjustment was insufficient. Therefore, the slice was insufficientlyresolved, and the flight distance was also relatively short. The example3 had excellent adjustability, and provided good results in resolutionof slice and a flight distance.

Example 4

A head having the adjusting mechanism M1 (loft angle adjustingmechanism) and the adjusting mechanism M4 (lie angle adjustingmechanism) was produced. A front member 4 and back member 6 of the headwere produced by a lost-wax precision casting using a titanium alloy(Ti-6Al-4V). The adjusting mechanism M4 was provided in a hosel part ofthe back member 6. A shaft (carbon shaft) and a grip were mounted to thehead, to obtain a golf club according to example 4. The golf club was anumber three wood golf club.

The example 4 was compared with the comparative examples 3 and 4. Thespecifications and evaluation results of the examples and comparativeexamples are shown in the following Table 3.

TABLE 3 Specifications and evaluation results of examples andcomparative examples Comparative Comparative Comparative Example Exampleexample 3 example 4-1 example 4-2 4-1 4-2 Loft angle (°) 16.5 17.5 15.517 16 Face angle (°) 3 5 1 3 3 Lie angle (°) 58.5 58 59 59 59.5 Distanceof center 30 30 30 30 30 of gravity (mm) Club length (inch) 42 42 42 4242 Balance D1 D1 D1 D1 D1 Ball initial speed 53 52.5 53 54 54 (m/s)Launch angle (°) 20 23 17 20 18 Backspin amount 3200 3500 3000 3100 2800(rpm) Side spin amount 1500 1000 2000 700 500 (rpm) Flight distance 170160 165 175 180 (yard) Directivity (yard) +25 +10 +40 +8 +5 Variablemechanism Loft Loft angle angle Lie Lie angle angle

The golf club of the example 4 was adjusted to a specification ofexample 4-1 shown in Table 3 using the adjusting mechanism, and wasevaluated. Furthermore, the golf club of the example 4 was adjusted to aspecification of example 4-2 shown in Table 3 using the adjustingmechanism, and was evaluated. The example 4 had excellent adjustability,and provided good results in resolution of slice and a flight distance.

Example 5

A head having the adjusting mechanism M1 (face angle adjustingmechanism), the adjusting mechanism M4 (lie angle adjusting mechanism),and the adjusting mechanism M5 (head-center-of-gravity positionadjusting mechanism) was produced. A front member 4 and back member 6 ofthe head were produced by a lost-wax precision casting using a titaniumalloy (Ti-6Al-4V). A screw hole of the adjusting mechanism M5 was formedin a sole part of the back member 6. The screw hole was produced by NCprocessing. The adjusting mechanism M4 was provided in a hosel part ofthe back member 6. A shaft (carbon shaft) and a grip were mounted to thehead, to obtain a golf club according to example 5. The golf club was anumber three wood golf club.

The example 5 was compared with the comparative examples 3 and 4. Thespecifications and evaluation results of the examples and comparativeexamples are shown in the following Table 4.

TABLE 4 Specifications and evaluation results of examples andcomparative examples Comparative Comparative Comparative Example Exampleexample 3 example 4-1 example 4-2 5-1 5-2 Loft angle (°) 16.5 17.5 15.516.5 16.5 Face angle (°) 3 5 1 5 6 Lie angle (°) 58.5 58 59 59 59Distance of 30 30 30 27 25 center of gravity (mm) Club length 42 42 4242 42 (inch) Balance D1 D1 D1 D1 D1 Ball initial speed 53 52.5 53 54 54(m/s) Launch angle 20 23 17 20 20 (°) Backspin 3200 3500 3000 3000 3000amount (rpm) Side spin 1500 1000 2000 500 200 amount (rpm) Flightdistance 170 160 165 188 195 (yard) Directivity +25 +10 +40 +0 −5 (yard)Variable Face Face mechanism angle angle Lie angle Lie angle DistanceDistance of center of center of of gravity gravity

The golf club of the example 5 was adjusted to a specification ofexample 5-1 shown in Table 4 using the adjusting mechanism, and wasevaluated. Furthermore, the golf club of the example 5 was adjusted to aspecification of example 5-2 shown in Table 4 using the adjustingmechanism, and was evaluated. The example 5 had excellent adjustability,and provided good results in resolution of slice and a flight distance.

Example 6

A head having the adjusting mechanism M1 (loft angle adjustingmechanism), the adjusting mechanism M4 (lie angle adjusting mechanism),and the adjusting mechanism M5 (head-center-of-gravity positionadjusting mechanism) was produced. A front member 4 and back member 6 ofthe head were produced by a lost-wax precision casting using a titaniumalloy (Ti-6Al-4V). A screw hole of the adjusting mechanism M5 was formedin a sole part of the back member 6. The screw hole was produced by NCprocessing. The adjusting mechanism M4 was provided in a hosel part ofthe back member 6. A shaft (carbon shaft) and a grip were mounted to thehead, to obtain a golf club according to example 6. The golf club was anumber three wood golf club.

The example 6 was compared with the comparative examples 3 and 4. Thespecifications and evaluation results of the examples and comparativeexamples are shown in the following Table 5.

TABLE 5 Specifications and evaluation results of examples andcomparative examples Comparative Comparative Comparative Example Exampleexample3 example 4-1 example 4-2 6-1 6-2 Loft angle (°) 16.5 17.5 15.517 16 Face angle (°) 3 5 1 3 3 Lie angle (°) 58.5 58 59 59 59.5 Distanceof 30 30 30 27 25 center of gravity (mm) Club length 42 42 42 42 42(inch) Balance D1 D1 D1 D1 D1 Ball initial 53 52.5 53 54 54 speed (m/s)Launch angle 20 23 17 20 18 (°) Backspin 3200 3500 3000 3100 2800 amount(rpm) Side spin 1500 1000 2000 700 500 amount (rpm) Flight distance 170160 165 175 180 (yard) Directivity +25 +10 +40 +0 −5 (yard) VariableLoft Loft mechanism angle angle Lie angle Lie angle Distance Distance ofof center center of of gravity gravity

The golf club of the example 6 can be adjusted to the specification ofthe comparative example 3. The golf club of the example 6 was adjustedto a specification of example 6-1 shown in Table 5 using the adjustingmechanism, and was evaluated. Furthermore, the golf club of the example6 was adjusted to a specification of example 6-2 shown in Table 5 usingthe adjusting mechanism, and was evaluated. The example 6 had excellentadjustability, and provided good results in resolution of slice and aflight distance.

Example 7

A head having the adjusting mechanism M1 (face angle adjustingmechanism) and the adjusting mechanism M3 (club length adjustingmechanism) was produced. A front member 4 and back member 6 of the headwere produced by a lost-wax precision casting using a titanium alloy(Ti-6Al-4V). The adjusting mechanism M3 was provided in a hosel part ofthe back member 6. A shaft (carbon shaft) and a grip were mounted to thehead, to obtain a golf club according to example 7. The golf club was anumber three wood golf club.

The example 7 was compared with the comparative examples 3 and 4. Thespecifications and evaluation results of the examples and comparativeexamples are shown in the following Table 6.

TABLE 6 Specifications and evaluation results of examples andcomparative examples Comparative Comparative Comparative Example Exampleexample 3 example 4-1 example 4-2 7-1 7-2 Loft angle (°) 16.5 17.5 15.516.5 16.5 Face angle (°) 3 5 1 5 6 Lie angle (°) 58.5 58 59 58.5 58.5Distance of 30 30 30 30 30 center of gravity (mm) Club length 42 42 4241.5 43 (inch) Balance D1 D1 D1 D4 D9 Ball initial 53 52.5 53 52.5 54speed (m/s) Launch angle 20 23 17 20 20 (°) Backspin 3200 3500 3000 28003000 amount (rpm) Side spin 1500 1000 2000 500 200 amount (rpm) Flight170 160 165 186 190 distance (yard) Directivity +25 +10 +40 0 +5 (yard)Variable Face Face mechanism angle angle Club Club length length

The golf club of the example 7 can be adjusted to the specification ofthe comparative example 3. The golf club of the example 7 was adjustedto a specification of example 7-1 shown in Table 6 using the adjustingmechanism, and was evaluated. Furthermore, the golf club of the example7 was adjusted to a specification of example 7-2 shown in Table 6 usingthe adjusting mechanism, and was evaluated. The example 7 had excellentadjustability, and provided good results in resolution of slice and aflight distance.

Example 8

A head having the adjusting mechanism M1 (loft angle adjustingmechanism) and the adjusting mechanism M3 (club length adjustingmechanism) was produced. A front member 4 and back member 6 of the headwere produced by a lost-wax precision casting using a titanium alloy(Ti-6Al-4V). The adjusting mechanism M3 was provided in a hosel part ofthe back member 6. A shaft (carbon shaft) and a grip were mounted to thehead, to obtain a golf club according to example 8. The golf club was anumber three wood golf club.

The example 8 was compared with the comparative examples 3 and 4. Thespecifications and evaluation results of the examples and comparativeexamples are shown in the following Table 7.

TABLE 7 Specifications and evaluation results of examples andcomparative examples Comparative Comparative Comparative Example Exampleexample 3 example 4-1 example 4-2 8-1 8-2 Loft angle (°) 16.5 17.5 15.517 15.5 Face angle (°) 3 5 1 3 3 Lie angle (°) 58.5 58 59 58.5 58.5Distance of 30 30 30 30 30 center of gravity (mm) Club length 42 42 4241.5 41.5 (inch) Balance D1 D1 D1 D4 D9 Ball initial 53 52.5 53 52 52speed (m/s) Launch angle 20 23 17 22 18 (°) Backspin 3200 3500 3000 32002800 amount (rpm) Side spin 1500 1000 2000 700 500 amount (rpm) Flight170 160 165 172 175 distance (yard) Directivity +25 +10 +40 +0 +0 (yard)Variable Loft Loft mechanism angle angle Club Club length length

The golf club of the example 8 can be adjusted to the specification ofthe comparative example 3. The golf club of the example 8 was adjustedto a specification of example 8-1 shown in Table 7 using the adjustingmechanism, and was evaluated. Furthermore, the golf club of the example8 was adjusted to a specification of example 8-2 shown in Table 7 usingthe adjusting mechanism, and was evaluated. Also in the test, theexample 8 had excellent adjustability, and provided good results inresolution of slice and a flight distance.

Example 9

A club having the adjusting mechanism M1 (face angle adjustingmechanism), the adjusting mechanism M3 (club length adjustingmechanism), the adjusting mechanism M5 (head-center-of-gravity distanceadjusting mechanism), and the adjusting mechanism M6 (swingweightadjusting mechanism) was produced. A front member 4 and back member 6 ofthe head were produced by a lost-wax precision casting using a titaniumalloy (Ti-6Al-4V). The adjusting mechanism M3 was provided in a hoselpart of the back member 6. A screw hole of the adjusting mechanism M5was formed in a sole part of the back member 6. A shaft grip assemblyhaving the adjusting mechanism M6 was mounted to the head, to obtain agolf club according to example 9. The golf club was a number three woodgolf club.

The example 9 was compared with the comparative examples 3 and 4. Thespecifications and evaluation results of the examples and comparativeexamples are shown in the following Table 8.

TABLE 8 Specifications and evaluation results of examples andcomparative examples Comparative Comparative Comparative Example Exampleexample 3 example 4-1 example 4-2 9-1 9-2 Loft angle (°) 16.5 17.5 15.516.5 16.5 Face angle (°) 3 5 1 5 6 Lie angle (°) 58.5 58 59 59 59Distance of 30 30 30 27 25 center of gravity (mm) Club length 42 42 4241.5 43 (inch) Balance D1 D1 D1 D1 D1 Ball initial 53 52.5 53 52.5 54speed (m/s) Launch angle 20 23 17 20 20 (°) Backspin 3200 3500 3000 28003000 amount (rpm) Side spin 1500 1000 2000 300 100 amount (rpm) Flight170 160 165 190 192 distance (yard) Directivity +25 +10 +40 −5 +0 (yard)Variable Face Face mechanism angle angle Club Club length length BalanceBalance Distance Distance of of center center of of gravity gravity

The golf club of the example 9 can be adjusted to the specification ofthe comparative example 3. The golf club of the example 9 was adjustedto a specification of example 9-1 shown in Table 8 using the adjustingmechanism, and was evaluated. Furthermore, the golf club of the example9 was adjusted to a specification of example 9-2 shown in Table 8 usingthe adjusting mechanism, and was evaluated. Also in the test, theexample 9 had excellent adjustability, and provided good results inresolution of slice and a flight distance.

Example 10

A club having the adjusting mechanism M1 (loft angle adjustingmechanism), the adjusting mechanism M3 (club length adjustingmechanism), the adjusting mechanism M5 (head-center-of-gravity distanceadjusting mechanism), and the adjusting mechanism M6 (swingweightadjusting mechanism) was produced. A front member 4 and back member 6 ofthe head were produced by a lost-wax precision casting using a titaniumalloy (Ti-6Al-4V). The adjusting mechanism M3 was provided in a hoselpart of the back member 6. A screw hole of the adjusting mechanism M5was formed in a sole part of the back member 6. A shaft grip assemblyhaving the adjusting mechanism M6 was mounted to the head, to obtain agolf club according to example 10. The golf club was a number three woodgolf club.

The example 10 was compared with the comparative examples 3 and 4. Thespecifications and evaluation results of the examples and comparativeexamples are shown in the following Table 9.

TABLE 9 Specifications and evaluation results of examples andcomparative examples Comparative Comparative Comparative Example Exampleexample 3 example 4-1 example 4-2 10-1 10-2 Loft angle (°) 16.5 17.515.5 17 15.5 Face angle (°) 3 5 1 3 3 Lie angle (°) 58.5 58 59 58.5 58.5Distance of 30 30 30 27 25 center of gravity (mm) Club length (inch) 4242 42 41.5 41.5 Balance D1 D1 D1 D1 D1 Ball initial speed 53 52.5 53 5353 (m/s) Launch angle (°) 20 23 17 22 18 Backspin amount 3200 3500 30003200 2800 (rpm) Side spin amount 1500 1000 2000 700 500 (rpm) Flightdistance 170 160 165 175 178 (yard) Directivity (yard) +25 +10 +40 −5 +0Variable Loft Loft mechanism angle angle Club Club length length BalanceBalance Distance Distance of center of center of gravity of gravity

The golf club of the example 10 can be adjusted to the specification ofthe comparative example 3. The golf club of the example 10 was adjustedto a specification of example 10-1 shown in Table 9 using the adjustingmechanism, and was evaluated. Furthermore, the golf club of the example10 was adjusted to a specification of example 10-2 shown in Table 9using the adjusting mechanism, and was evaluated. The example 10 hadexcellent adjustability, and provided good results in resolution ofslice and a flight distance.

Example 11

A golf club provided with the adjusting mechanism M7 and the adjustingmechanism M8 was produced.

The adjusting mechanism M7 was provided with two sleeves Sv having theinclination angle θ1 of 0 degree. Positions of shaft insertion holes 150were made different between the two sleeves Sv. In the first sleeve Sv,an axis line of the shaft insertion hole 150 was coaxial with a centralaxis line of a sleeve outer surface. On the other hand, in the secondsleeve Sv, the axis line of the shaft insertion hole deviated from thecentral axis line of the sleeve outer surface. That is, in the secondsleeve Sv, the shaft insertion hole was eccentric.

The adjusting mechanism M8 was provided with two changing back membersE8 having different positions of centers of gravity.

In the golf club according to the example 11, a face progression couldbe changed by changing the sleeve Sv. A lie angle, a face angle, and aloft angle were not varied by changing the sleeve Sv. Furthermore, inthe golf club, a position of a center of gravity of a head could bechanged by changing the changing back members E8. In the golf club, theface progression and the position of the center of gravity of the headcould be adjusted independently of each other.

Example 12

A golf club provided with the adjusting mechanism M1 and the adjustingmechanism M9 was produced.

The adjusting mechanism M1 was provided with two changing front membersE4 which are different only in the loft angles.

The adjusting mechanism M9 was provided with two outer side grip members196 having different thicknesses.

In the golf club according to the example 12, a loft angle could bechanged by changing the changing front member E4. A face angle was notvaried by changing the changing front member E4. Furthermore, in thegolf club, a thickness of a grip could be changed by changing the outerside grip member 196. In the golf club, the loft angle and the thicknessof the grip could be adjusted independently of each other.

Example 13

A golf club provided with the adjusting mechanism M1 and the adjustingmechanism M10 was produced.

The adjusting mechanism M1 was provided with two changing front membersE4 which are different only in the face angles.

The adjusting mechanism M10 was provided with one extending member 252b.

In the golf club according to the example 13, a face angle could bechanged by changing the changing front member E4. A loft angle was notvaried by changing the changing front member E4. Furthermore, in thegolf club, a club length could be changed by mounting/demounting theextending member 252 b. The face angle and the club length could beadjusted independently of each other.

Example 14

A golf club provided with the adjusting mechanism M1 and the adjustingmechanism M11 was produced. An exploded perspective view of a headaccording to example 14 is the same as that of the head 268 shown inFIGS. 33 and 34.

In the example 14, a front member can be changed, and an adjustingintermediate member can be also changed. A face angle and a loft anglecan be adjusted by changing only the front member. The face angle andthe loft angle can be adjusted by changing only the adjustingintermediate member. Furthermore, various adjustments are enabled bycombining the front members with the adjusting intermediate members.

Example 15

A golf club provided with the adjusting mechanism M1 and the adjustingmechanism M6 was produced.

The adjusting mechanism M1 was provided with two changing front membersE4 which are different only in the face angles (see FIG. 3).

The adjusting mechanism M6 was provided with a plurality of weightbodies Wg having different weights in relation to each other (see FIG.17).

In the golf club according to the example 15, a face angle could bechanged by changing the changing front member E4. Furthermore, in thegolf club, a swingweight could be changed by changing andmounting/demounting the weight body Wg. The face angle and theswingweight could be adjusted independently of each other.

Example 16

A golf club provided with the adjusting mechanism M1 and the adjustingmechanism M8 was produced.

A head according to the example 16 was the same as the above-mentionedhead 170 (see FIGS. 24 and 25).

In the example 16, a plurality of front members 172 shown in FIG. 24 wasprepared as the adjusting mechanism M1. The plurality of front members172 had different face angles in relation to each other. Furthermore, inthe example 16, a plurality of back members 174 having different volumesin relation to each other was prepared as the adjusting mechanism M8.

In the golf club according to the example 16, a face angle could bechanged by changing the front member 172. Furthermore, in the golf club,a head volume (a depth of a center of gravity and a moment of inertia ofthe head) could be changed by changing the back member 174. The faceangle and the head volume (the depth of a center of gravity and themoment of inertia of the head) could be adjusted independently of eachother.

Example 17

A golf club provided with the adjusting mechanism M1 and the adjustingmechanism M10 was produced.

The adjusting mechanism M1 was provided with two front members E4 whichare different only in the face angles (see FIG. 3).

The adjusting mechanism M10 was provided with two extending members 252b having an identical shape in relation to each other (see FIG. 31).

In the golf club according to the example 17, a face angle could bechanged by changing the changing front member E4. Furthermore, in thegolf club, a club length (swingweight) could be changed by the number ofthe mounted extending members 252 b. The face angle and the club length(swingweight) could be adjusted independently of each other.

Example 18

A golf club provided with the adjusting mechanism M5 and the adjustingmechanism M6 was produced.

The adjusting mechanism M5 was provided with one weight body 104 (seeFIG. 14).

The adjusting mechanism M6 was provided with a plurality of weightbodies Wg having different weights in relation to each other (see FIG.17).

In the golf club according to the example 18, a position of a center ofgravity of a head could be changed by changing a position of the weightbody 104. Furthermore, in the golf club, a swingweight could be changedby changing and mounting/demounting the weight body Wg. The position ofthe center of gravity of the head and the swingweight could be adjustedindependently of each other.

Example 19

A golf club provided with the adjusting mechanism M5 and the adjustingmechanism M8 was produced.

A basic structure of a head according to the example 19 was set as shownin FIG. 24. Furthermore, a plurality of disposing holes Wh (see FIG. 15)was formed in a front member 172 (see FIG. 24) of the head. That is, theadjusting mechanism MS was provided in the front member 172. Theadjusting mechanism M5 may be provided in the back member 174 (see FIG.24). That is, a plurality of disposing holes Wh (see FIG. 15) maybeformed in the back member 174.

The adjusting mechanism M5 was provided with one weight body 104 (seeFIG. 14).

The adjusting mechanism M8 was provided with a plurality of back member174 having different volumes (see FIG. 24).

In the golf club according to the example 19, a position of a center ofgravity of the head could be changed by changing a position of theweight body 104. Furthermore, in the golf club, a head volume could bechanged by changing the back member 174. The position of the center ofgravity of the head and the head volume could be adjusted independentlyof each other.

On the other hand, the position of the center of gravity of the head wasalso varied by the adjusting mechanisms M5, and was also varied by theadjusting mechanisms M8. Therefore, the position of the center ofgravity of the head could be variously adjusted. That is, a high degreeof freedom was achieved in adjustment of the position of the center ofgravity of the head.

Example 20

A golf club provided with the adjusting mechanism M5 and the adjustingmechanism M9 was produced.

The adjusting mechanism M5 was provided with one weight body 104 (seeFIG. 14).

The adjusting mechanism M9 was provided with a plurality of outer sidegrip members 196 having different thicknesses (see FIGS. 27 and 28).

In the golf club according to the example 20, a position of a center ofgravity of a head could be changed by changing a position of the weightbody 104. Furthermore, in the golf club, a thickness of a grip could bechanged by changing the outer side grip member 196. In the golf club,the position of the center of gravity of the head and the thickness ofthe grip could be adjusted independently of each other.

Example 21

A golf club provided with the adjusting mechanism M5 and the adjustingmechanism M10 was produced.

The adjusting mechanism M5 was provided with one weight body 104 (seeFIG. 14).

The adjusting mechanism M10 was provided with two extending members 252b having an identical shape in relation to each other (see FIG. 31).

In the golf club according to the example 21, a position of a center ofgravity of a head could be changed by changing a position of the weightbody 104. Furthermore, in the golf club, a club length (grip length andswingweight) could be changed by the number of the mounted extendingmembers 252 b. The position of the center of gravity of the head and theclub length (grip length and swingweight) were adjusted independently ofeach other.

Example 22

A golf club provided with the adjusting mechanism M6 and the adjustingmechanism M8 was produced.

The adjusting mechanism M6 was provided with a plurality of weightbodies Wg having different weights in relation to each other (see FIG.17).

The adjusting mechanism M8 was provided with a plurality of back members174 having different shapes (see FIGS. 24 and 25).

In the golf club according to the example 22, a swingweight was changedby mounting/demounting and changing the weight body Wg. Furthermore, inthe golf club, a head shape could be changed by changing the back member174. The swingweight and the head shape were adjusted independently ofeach other.

Example 23

A golf club provided with the adjusting mechanism M6 and the adjustingmechanism M9 was produced.

The adjusting mechanism M6 was provided with a plurality of weightbodies Wg having different weights in relation to each other (see FIG.17).

The adjusting mechanism M9 was provided with a plurality of outer sidegrip members 196 having different thicknesses (see FIGS. 27 and 28).

In the golf club according to the example 23, a swingweight was changedby mounting/demounting and changing the weight body Wg. Furthermore, inthe golf club, a grip outer diameter was changed by changing the outerside grip member 196. The swingweight and the grip outer diameter wereadjusted independently of each other.

Example 24

A golf club provided with the adjusting mechanism M6 and the adjustingmechanism M10 was produced.

FIG. 36 is an exploded view of a grip part of the golf club according tothe example 24. The golf club has the above-mentioned grip 252 (see FIG.31). Furthermore, the golf club has two weight bodies Wg.

A first weight body Wg1 has a head part 300 and a body part 302. Thehead part 300 is a disk-shaped. The body part 302 is a male screw. Thehead part 300 is coaxial with the body part 302. A second weight bodyWg2 has a head part 300 and a body part 306. The body part 306 is a malescrew. The head part 300 is coaxial with the body part 306. An axiallength of the body part 302 is different from that of the body part 300.The difference causes a weight difference between the weight body Wg1and the weight body Wg2.

The body parts 302 and 306 of the weight body Wg conforms to a screwhole sc4 of the extending member 252 b. The body parts 302 and 306 canbe screwed into the screw hole sc4.

The adjusting mechanism M10 in the example 24 is the same as that of theembodiment of FIG. 30. On the other hand, the adjusting mechanism M6 inthe example 24 is different from that of the embodiment of FIG. 17. Theadjusting mechanism M6 includes the weight body Wg and the extendingmember 252 b as shown in FIG. 36. A swingweight can be adjusted bymounting any of the weight bodies Wg to the extending member 252 b. Theswingweight can be adjusted by presence or absence of the mounted weightbody Wg.

In the golf club according to the example 24, the swingweight waschanged by mounting/demounting and changing the weight body Wg.Furthermore, in the golf club, the swingweight and a club length werechanged by the number of the mounted extending members 252 b. In theexample 24, the club length can be adjusted. In the example 24, theswingweight could be variously adjusted by a combinations of theextending member 252 b and the weight body Wg.

Example 25

A golf club provided with the adjusting mechanism M8 and the adjustingmechanism M9 was produced.

The adjusting mechanism M8 was provided with two backmembers 174 havingdifferent positions of centers of gravity (see FIGS. 24 and 25).

The adjusting mechanism M9 was provided with a plurality of outer sidegrip members 196 having different thicknesses (see FIGS. 27 and 28).

A position of a center of gravity of a head was changed by changing theback member 174 in the golf club according to the example 25.Furthermore, in the golf club, a grip outer diameter was changed bychanging the outer side grip member 196. The position of the center ofgravity of the head and the grip outer diameter were adjustedindependently of each other.

Example 26

A golf club provided with the adjusting mechanism M8 and the adjustingmechanism M10 was produced.

The adjusting mechanism M8 was provided with two backmembers 174 havingdifferent positions of centers of gravity (see FIGS. 24 and 25).

The adjusting mechanism M10 was provided with two extending members 252b having an identical shape in relation to each other (see FIG. 31).

In the golf club according to the example 26, a position of a center ofgravity of a head was changed by changing the back member 174.Furthermore, in the golf club, a swingweight and a club length werechanged by the number of the mounted extending members 252 b. Theposition of the center of gravity of the head and the swingweight (clublength) were adjusted independently of each other.

Example 27

A golf club provided with the adjusting mechanism M6 and the adjustingmechanism M12 was produced.

The adjusting mechanism M6 was provided with a plurality of weightbodies Wg having different weights in relation to each other (see FIG.17).

The adjusting mechanism M12 was provided with a plurality of frontmembers 282 having different loft angles in relation to each other (seeFIG. 35).

In the golf club according to the example 27, a swingweight was changedby changing the weight body Wg. Furthermore, in the golf club, a loftangle was changed by changing the front member 282. The swingweight andthe loft angle were adjusted independently of each other.

Example 28

A golf club provided with the adjusting mechanism M10 and the adjustingmechanism M12 was produced.

The adjusting mechanism M10 was provided with two extending members 252b having an identical shape in relation to each other (see FIG. 31).

The adjusting mechanism M12 was provided with a plurality of frontmembers 282 having different loft angles in relation to each other (seeFIG. 35).

In the golf club according to the example 28, a club length(swingweight) was changed by the number of the mounted extending members252 b. Furthermore, in the golf club, a loft angle was changed bychanging the front member 282. The club length (swingweight) and theloft angle were adjusted independently of each other.

The combination of the adjusting mechanisms is not restricted to thecombinations in these examples. The number of the combinations of theadjusting mechanisms is not also restricted. For example, any twoselected from the adjusting mechanisms M1 to M12 can be combined. Anythree selected from the adjusting mechanisms M1 to M12 can be combined.

The invention described above can be applied to all golf clubs such as awood type, utility type, hybrid type, iron type, and putter type golfclubs.

The description hereinabove is merely for an illustrative example, andvarious modifications can be made in the scope not to depart from theprinciples of the present invention.

What is claimed is:
 1. A golf club comprising: a head; a shaft; and agrip; wherein the head includes a front member and a back memberdetachably mounted to the front member.
 2. The golf club according toclaim 1, wherein the head further includes a connecting memberconnecting the front member to the back member.
 3. The golf clubaccording to claim 2, wherein the connecting member includes at leastone screw.
 4. The golf club according to claim 3, wherein the frontmember has at least one screw hole into which the at least one screw isscrewed.
 5. The golf club according to claim 4, wherein the back memberhas at least one through hole through which the at least one screwpasses into the at least one screw hole of the front member.
 6. The golfclub according to claim 1, wherein the front member has a hosel parthaving a shaft hole into which the shaft is inserted.
 7. The golf clubaccording to claim 1, wherein the front member has an extending partsupporting an inner side of an edge part of the back member.
 8. The golfclub according to claim 7, wherein the extending part of the frontmember is located at an edge of an opening of the front member.
 9. Thegolf club according to claim 1, wherein the back member is press fittedinto the front member.
 10. The golf club according to claim 9, whereinthe back member has an engagement protruding part with an engaginggroove, and the engagement protruding part of the back member is pressfitted into an opening part of the front member.
 11. The golf clubaccording to claim 9, wherein the front member has an inner extendingpart fitted into the engaging groove of the engagement protruding partof the back member to connect the front member to the back member. 12.The golf club according to claim 9, wherein the engagement protrudingpart of the back member has an inclined surface facilitating pressfitting of the back member into the front member.
 13. The golf clubaccording to claim 1, wherein one or more disposing holes are formed inthe front member or the back member for receiving one or more weightbodies.